In Foobar2000's (on Android) change logs there's an entry regarding optionally excluding .nomedia files :
Version 1.0.74, 2017-05-22
.nomedia folder exclusion is now opt-out.
I have a .nomedia file in my music directory and would like to tell Foobar2000 to ignore this - where to find the option ?
Found it :D : Settings > Advanced > Exclude folders with .nomedia from indexing