Control the display order of tag groups lists in the collection sidebar using Supply's 'advanced tag filtering' - and control the sort order of the list items within that group using a link list.

readme.md

Group Sorting:

• There is a text field in the theme settings where you list the tag prefixes with no underscores. (ex: Size,Price,Color)
• All groups must be mentioned in that input field in order to appear, if no groups are mentioned then it will go in alphabetical order.

Individual List Sorting:

• This requires the use of a Link List in the Navigation area of the Admin
• The list name is 'reorder_' with the tag prefix to represent the group of tags you want to manually sort. ie Reorder_Size
• Each link inside this list is the full product tag with prefix and underscore directly the same as in the product page.
• Only the lists that you want to sort manually need to be created or else it will just use the normal sorting of the list
• See image below as an example:

collection-sidebar.liquid

<div class="grid-uniform">
  {% assign group_array = settings.group_array | split: ',' %}
  {% for group in group_array %}
    {% if cat_array contains group %}
      {% capture array %}{% unless array == blank or array == "" %}{{ array }},{% endunless %}{{group | strip}}{% endcapture%}
    {% endif %}
  {% endfor%}
  {% assign cat_array = array | split:',' %}
  
  {% comment %}
  If the theme setting for group array is empty then use the default cat_array order
  {% endcomment %}
  
  {% if group_array == blank %}
    {% assign group_array = cat_array %}
  {% endif %}
  
  {% comment %}
  Loop through tag categories
  {% endcomment %}
  {% for cat_item in group_array %}
    {% assign tags_present = false %}
    
    {% if cat_array contains cat_item %}
      {% assign tags_present = true %}
    {% endif %}
    {% unless tags_present == false %}
      {% assign linklist_title = cat_item | handleize | prepend: 'reorder_' %}
      {% if linklists[linklist_title].links != '' %}
      <div class="grid-item small--one-half medium--one-third">
        <h3>{{ cat_item }}</h3>
        <ul class="advanced-filters">
          {% comment %}
            Loop through collection tags
          {% endcomment %}
          
          {% for link in linklists[linklist_title].links %}
            {% for tag in collection.all_tags %}
              {% if tag contains link.title %}
                {% assign cat = tag | split: '_' | first %}              
                {% if cat != tag and cat_item == cat %}
                  {% comment %}
                    Strip out tag category prefix and add/remove link for tag filtering
                  {% endcomment %}
                  {% if current_tags contains tag %}
                    <li class="advanced-filter active-filter" data-group="{{ cat_item }}" data-handle="{{ tag | handle }}">{{ tag | remove_first: cat_item | remove_first: '_' | link_to_remove_tag: tag }}</li>
                  {% else %}
                    <li class="advanced-filter" data-group="{{ cat_item }}" data-handle="{{ tag | handle }}">{{ tag | remove_first: cat_item | remove_first: '_' | link_to_add_tag: tag }}</li>
                  {% endif %}
                {% endif %}
              {% endif %}
            {% endfor %}
          {% endfor %}
        </ul>
      </div>
      {% endif %}
      {% unless cat_item == '' or linklists[linklist_title].links.size > 0  %}
        <div class="grid-item small--one-half medium--one-third">
          <h3>{{ cat_item }}</h3>
          <ul class="advanced-filters">
            {% comment %}
              Loop through collection tags
            {% endcomment %}
            {% for tag in collection.all_tags %}
              {% assign cat = tag | split: '_' | first %}              
              {% if cat != tag and cat_item == cat %}
                {% comment %}
                  Strip out tag category prefix and add/remove link for tag filtering
                {% endcomment %}
                {% if current_tags contains tag %}
                  <li class="advanced-filter active-filter" data-group="{{ cat_item }}" data-handle="{{ tag | handle }}">{{ tag | remove_first: cat_item | remove_first: '_' | link_to_remove_tag: tag }}</li>
                {% else %}
                  <li class="advanced-filter" data-group="{{ cat_item }}" data-handle="{{ tag | handle }}">{{ tag | remove_first: cat_item | remove_first: '_' | link_to_add_tag: tag }}</li>
                {% endif %}
              {% endif %}
            {% endfor %}
          </ul>
        </div>
      {% endunless %}
    {% endunless %}
  {% endfor %}
</div>

settings_schema.json

{
  "type": "text",
  "label": "Type the sidebar's tag groups in a comma-separated list.",
  "id": "group_array",
  "info": "List items must be identical to the tag prefixes (no underscore), and have no spaces between commas.ie. Brand,Product Type,Burn Time (approx),Colour"
}