Thanks for the extensive help, this really helps. And wishing you the same, enjoy the holidays and or Christmas! Prettige Kerstdagen (in Dutch), Happy Christmas! 
I can also transform the XML files to JSON with a tool. (and to be honest, it was also +10 years that I used XML). Let’s have a look at the links you provide (again, really appreciate it!). How can I loop a list of JSON files in a folder? This is from the Jekyll Docs
<ul>
{% for org_hash in site.data.orgs %}
{% assign org = org_hash[1] %}
<li>
<a href="https://github.com/{{ org.username }}">
{{ org.name }}
</a>
({{ org.members | size }} members)
</li>
{% endfor %}
</ul>
Process
This process is in my head. The magic from paper to XML/CSV (and even XSL) comes from Nanonets. Their service for OCR from PDF files is great (and free for smaller projects)
