I ran your post through Firefox translate, please forgive my sad state of being a (mostly) monolingual English speaker (besides some Amharic and Arabic). Yes lots of translation issues for Firefox but it can help get some understanding I hope.
Yes that is best if possible. Then we can know if a thread can be marked “solved”.
As noted, I used a translation tool. I see several posting questions in French or German with an English translation below. I don’t know how possible this would be for you. It would increase the chances for a reply if possible.
Sorry I am not certain, but the GSI Wiki thread is probably where to look for more info.
Personally, I think if the base android version matches it should be fine, and I don’t think (??) it will require a userdata wipe, but do have a backup first, and be ready to do a full reset and install if you experience issues.
Sorry I have not read the GSI thread very closely at all. But if you can crawl around the internet and find an unofficial Lineage build with sources then it may be possible to make an unofficial iodéOS build, but no guarantees.
Good luck!