https://htd-doma.tumblr.com/

htd.js

const {join} = require('path')
const {readdir} = require('fs').promises
const id3 = require('node-id3')
const iconv = require('iconv-lite')

const songs = f => f.isFile() && f.name.endsWith('.mp3')
const albums = f => f.isDirectory() && f.name.startsWith('HTD')
const ls = iconv.skipDecodeWarning = p => readdir(p, {withFileTypes: true})

async function* patch (path) {
  for (const {name: album} of (await ls(path)).filter(albums)) {
    for (const {name: song} of (await ls(album)).filter(songs)) {
      const file = join(album, song)
      const {raw, ...tags} = id3.read(file)
      const title = iconv.decode(tags.title, 'Shift_JIS')
      yield {file, title, success: id3.update({...tags, title}, file)}
    }
  }
}

(async () => {for await (const p of patch('.')) console.log(p)})()

package.json

{
  "dependencies": {
    "iconv-lite": "^0.5.1",
    "node-id3": "^0.1.16"
  }
}