Problem Export in Blender

[TheBatmanLP]

Hello, materials is ok but in export is showing error that you see on image do you know what can i do with it please? Thanks.

[AlexeyP]

do you know what can i do with it please?

My guess is that you use non-english letters (you use Czech right?) somewhere in blender. It may be the name of mesh object, variant name, look name, part name, name of some texture or material, path to your mod or something like else. So i suggest you to rename everything to english names.
Also, i see that you have Steam Blender version and it is installed in D:\Hry ze steamu folder. Maybe Blender doesn't like when folder has spaces in it. So it is worth to try and rename 'hry ze steamu' into something like 'steam_games' or something like this.

[Etrusan]

Stick to a-z, 0-9 and underscores only (model names, texture names, folders, etc.). Nothing else. Spaces in the path to Blender shouldn't cause any problems as by default Blender is installed under "C:\Program Files\Blender Foundation\Blender 2.91".