How did you eventually get this to clear if you did? Full restart or something else?
Yes, I solved it.
First, I copied the files again from programs x86 in the original installation, the one for my main account, which wasn't buggy, to the folder for my second account.
Same thing
So at this point, we already know that it's not a hardware issue.
I noticed that when I log in for the first time on a character from the second account, after (re)launching the game, this bug occurs once I select a mercenary hero from the group. It crashes and then spreads like a virus to my non-mercenary heroes.
In short, I wanted to delete all the mercenaries on the main character of the secondary account. Before when I remove the runes from these mercenaries, the icons return to normal (but not overall, just when I do it...). I removed all the runes and weapons from all the mercenaries. Then I quit (restarted the game or the character) and nothing happened, not bug. You have to do this for each character with all these mercenaries, just in case. Then, after seeing that it worked and that I couldn't find the bug, I re-equipped everything. Everything is working normally again.
My theory?
I have sometimes changed the names and appearances of mercenaries without deleting them. Let me explain... I have a mercenary in slot 3 with the NPC [Mercenary Registrar]. I create a PvP character with the same profession as the one I'm going to delete in order to change its appearance and name. So I delete the mercenary from slot 3 and replace it with the one I created. Since it has the same profession, there's no need to remove the runes and weapons. I think the game misinterpreted this at some point.
Or not
In any case, removing the runes and weapons from all mercenary heroes, logging out, then re-equipping everything works.