Hello limorzz & Welcome to bitcointalk.
By having time searching about privacy in the blockchain, did you check how mixers work and CoinJoin feature?
I realize that a crypto like this very likely doesn't exist currently, however I'd be happy with any recommendations that'd even come near this, I had been thinking of founding something like it myself and really making it my lifes worth as I believe it should be possible but it just needs the right people to do the right things.
A new protocol called Mimble-Wimble (unknown inventor like bitcoin) was in reach for Devs since few years but not many have tried to use it due to several technical reasons. This protocol allows for hidden transaction within the explorer with no addresses for both sender and receiver neither the amount can be shown, both sender and receiver have to sign the transaction or using another protocol, the idea is not that complex if you look into it deeply.
See:
https://github.com/mimblewimbleI remember read how to combine this protocol with the blockchain of bitcoin but it seems to be an upcoming step and no urgent need for it actually.
In the other side, recently few projects have been lunched with this protocol and the looks as they are doing well as they are all in development phase. I am giving you two examples:
Grin Coin:
https://grin.mw/BEAM:
https://beam.mw/