Impossible to export multiple fbx

Hello, i got a problem, I exported a low poly character in FBX whitout problem and now i want to export the high poly character in FBX I got an error about the fbx export addon and something about an array

here is the screen, i don’t understand where this error come from
I use blender 2.90 but i test in previous version i got the same error

first time i’m posting here sorryif i’m missing something
Thanks for your time.