Hi Sebastian,
I don’t agree with the donk-bet on the flop. I think you should be checking basically everything to the aggressor because trying to come up with a balanced donk-bet strategy is very difficult. Also, the BTN has way more nutted hands (AJ, AA,KK,QQ,TT etc) than we do. Check raising is probably best here. Also, your bet size of almost pot is very large. I think going with 0.18 or so is a bit better.
Turn: I think you should be checking. Since betting the flop put you in a weird position ( you’re not really betting for value or as a bluff) you should be check calling.
River: Villain shoves for 2x pot. You basically have a bluff catcher now because you’re probably chopping at best and I think you should be folding. There’s not many hands villain will be bluffing with here that called the flop and turn, and there’s a lot of flushes you can be up against. Although it’s possible villain might raise some on the flop or turn.
Please let me know if you disagree at all.