Might I suggest you join one of the established wargaming clubs? There, you will readily find opponents for PBEM.
(This site has multi-lingual sections, btw, in English, Czech, Polish etc. etc.)
I'm sure you'll be made welcome, whichever one you choose.
If you don't want your games to be recorded on the Ladders, that's OK. Just advise your Opponents when agreeing the parameters of the Game.