Subj.

 

I tried set name in EOF, press N, "Edit Pro guitars notes" set there name Amaj7

In preview 3D window show right

Clear fingering, set new fingering, generate fret position and..

In game it show as Am7.

 

Any ideas?

In EOF, it's possible to author it so that one instance of a chord can be manually named and leave it so that other instances of the same chord have a different name. You can manually rename all instances of that chord (on a per track difficulty basis) by selecting one of them, using "Select like" (CTRL+L) and using "Note>Edit name" to change the names and leave everything else about the chords as-is.