I am still investigating potential causes of the problem I have spotted at
Comments from (commented !) games lost in "ChessBase to Scid on the go" conversion process
So, in ChessBase 15, in "File --> Options --> Languages" the alternative annotation language is set as follows by default to "Deutsch" :
If I change it to English, click apply, close ChessBase 15 an reopen it, by some kind of supranatural miracle of nature, the alternative annotation language is again equal to Deutsch. Bonus : even if I only close the options windows and reopen it, I will "Deutsch" again for the alternative annotation language. Isn't it beautiful ?
As I am still not desperate about this software, would someone have an idea ?