Filter to highlight some authors in the bibliography

highlight-author.lua

local List = require 'pandoc.List'
local utils = require 'pandoc.utils'
local stringify = utils.stringify

function highlighter(given_name_pattern, family_name_pattern)
  local highlight_author = function (author)
    local given = author.given and stringify(author.given)
    local family = author.family and stringify(author.family)
    if given and given:match(given_name_pattern) and
       family and family:match(family_name_pattern) then
      author.given = {pandoc.Strong(setmetatable(author.given, nil))}
      author.family = {pandoc.Strong(setmetatable(author.family, nil))}
    end
    return author
  end
  return function(reference)
    if reference.author and reference.author.map then
      reference.author = reference.author:map(highlight_author)
    end
    return reference
  end
end

function Pandoc (doc)
  local meta = doc.meta
  local fh = io.popen(
    "pandoc-citeproc --bib2yaml "
      .. stringify(meta.bibliography)
  )
  if io.type(fh) ~= 'file' then return end

  local bibyaml = fh:read('*a')
  fh:close()

  local references = pandoc.read(bibyaml).meta.references
  meta.bibliography = nil

  meta.references = references:map(
    highlighter(stringify(meta['given-name-pattern']),
                stringify(meta['family-name-pattern']))
  )

  return utils.run_json_filter(
    pandoc.Pandoc(doc.blocks, meta),
    'pandoc-citeproc'
  )
end

The highlight-author.lua filter only works with old versions of pandoc that use pandoc-citeproc. The other filter should work, but you have to be careful about how your name and initials are output by the csl you are using. Try converting to a .json file first to see how your csl treats initials, commas, periods, etc and make sure that you copy the strings correctly into the filter. I did a quick search in Scopus for Ayhan and created a short bibliography to test (as .json file, can also be .bib) - not sure if this is you, but you can adjust accordingly. I include below a text with two references (save as test.txt), the lua filter modified with your name (save as test.lua), the bibliography (save as biblio.json) and a csl file that I use to create a cv with my name underlined (so it puts all the details in the citation, not in a bibliography at the end - save as CiteOnly.csl). The command:

pandoc --citeproc --bibliography=biblio.json --csl=CiteOnly.csl -L test.lua -o test.pdf test.txt

should give you the correct result with name underlined - or use -o test.html if you don't want pdf. Then try with your csl file, if it doesn't work, convert to .json (pandoc -t json etc.), check how your initials are formated and adjust the lua filter.

Files:
test.txt

@Ayhan2022872

@Varpahovskis202252

test.lua

function Inline (el)
  if el.t == "Cite" then
    for k,_ in ipairs(el.content) do

      if el.content[k].t == "Str" and el.content[k].text == "Ayhan,"
      and el.content[k+1].t == "Space"
      and el.content[k+2].t == "Str" and el.content[k+2].text:find("^K.J.") then

          local _,e = el.content[k+2].text:find("^K.J.")
          local rest = el.content[k+2].text:sub(e+1) 
          el.content[k] = pandoc.Underline { pandoc.Str("Ayhan, K.J.") }
          el.content[k+1] = pandoc.Str(rest)
          table.remove(el.content, k+2) 
      end
    end
  end
  return el
end

biblio.json

[
	{
		"id": "Ayhan2022872",
		"type": "article-journal",
		"container-title": "Journal of Asian and African Studies",
		"DOI": "10.1177/00219096211035800",
		"issue": "4",
		"note": "tex.document_type: Article\ntex.source: Scopus",
		"page": "872-893",
		"title": "Exploring global korea scholarship as a public diplomacy tool",
		"URL": "https://www.scopus.com/inward/record.uri?eid=2-s2.0-85112764468&doi=10.1177%2f00219096211035800&partnerID=40&md5=b0445b994fdf178b3635cd521b10abe9",
		"volume": "57",
		"author": [
			{
				"family": "Ayhan",
				"given": "K.J."
			},
			{
				"family": "Gouda",
				"given": "M."
			},
			{
				"family": "Lee",
				"given": "H."
			}
		],
		"issued": {
			"date-parts": [
				[
					"2022"
				]
			]
		}
	},
	{
		"id": "Varpahovskis202252",
		"type": "article-journal",
		"container-title": "Place Branding and Public Diplomacy",
		"DOI": "10.1057/s41254-020-00177-0",
		"issue": "2",
		"note": "tex.document_type: Article\ntex.source: Scopus",
		"page": "52-64",
		"title": "Impact of country image on relationship maintenance: a case study of Korean Government Scholarship Program alumni",
		"URL": "https://www.scopus.com/inward/record.uri?eid=2-s2.0-85089368484&doi=10.1057%2fs41254-020-00177-0&partnerID=40&md5=5f1f27dc8b88674ee4d38560f1d2eab9",
		"volume": "18",
		"author": [
			{
				"family": "Varpahovskis",
				"given": "E."
			},
			{
				"family": "Ayhan",
				"given": "K.J."
			}
		],
		"issued": {
			"date-parts": [
				[
					"2022"
				]
			]
		}
	}
]

CiteOnly.csl

<?xml version="1.0" encoding="utf-8"?>
<style xmlns="http://purl.org/net/xbiblio/csl" version="1.0" class="in-text" default-locale="en-US" demote-non-dropping-particle="sort-only" page-range-format="expanded">
  <info>
    <title>CiteOnly</title>
  </info>
  <macro name="author-short">
    <names variable="author">
      <name form="short" and="text"/>
    </names>
  </macro>
  <macro name="author-count">
    <names variable="author">
      <name form="count"/>
    </names>
  </macro>
  <macro name="author">
    <names variable="author">
      <name name-as-sort-order="all" initialize-with="." and="text" delimiter-precedes-last="always"/>
    </names>
  </macro>
  <macro name="issued">
    <date variable="issued">
      <date-part name="year"/>
    </date>
  </macro>
  <macro name="publisher">
    <group prefix="(" delimiter=": " suffix=")">
      <text variable="publisher-place"/>
      <text variable="publisher"/>
    </group>
  </macro>
  <macro name="editor">
    <names variable="editor">
      <name initialize-with="." and="text" delimiter-precedes-last="always"/>
      <label form="short" prefix=", "/>
    </names>
  </macro>
  <citation et-al-min="21" et-al-use-first="20">
    <sort>
      <key macro="author-short" names-min="1" names-use-first="1"/>
      <key macro="author-count" names-min="3" names-use-first="3"/>
      <key macro="author" names-min="3" names-use-first="1"/>
      <key macro="issued"/>
      <key variable="title"/>
    </sort>
    <layout suffix=".">
      <group delimiter=" ">
        <text macro="author"/>
        <text macro="issued" prefix="(" suffix=")."/>
        <choose>
          <if type="article article-magazine article-newspaper article-journal review" match="any">
            <text variable="title" suffix="."/>
            <text variable="container-title" form="short" text-case="title" font-weight="bold"/>
            <group delimiter=", ">
              <text variable="volume" font-style="italic"/>
              <text variable="page"/>
            </group>
          </if>
          <else-if type="chapter paper-conference" match="any">
            <text variable="title" suffix="."/>
            <text variable="container-title" prefix="In " suffix="," text-case="title"/>
            <text macro="editor"/>
            <text macro="publisher" suffix=","/>
            <label variable="page" form="short"/>
            <text variable="page"/>
          </else-if>
          <else-if type="thesis">
            <text variable="title" suffix="."/>
            <text variable="genre" suffix="."/>
            <text variable="publisher"/>
          </else-if>
          <else>
            <text variable="title"/>
            <text macro="publisher"/>
          </else>
        </choose>
      </group>
    </layout>
  </citation>
</style>

Thank you very much for very detailed instructions. I should have probably mentioned that I am a markdown novice. And this is first time touching a lua file. I tried adding test.lua to my folder and to _output.yml here, but it didn't produce any result either (probably I should change something more).