I would go with blackjack. With a little bit of luck I might win that 20% in less than 5 hours. Sportsbetting would be a good choice if I'd have more time, 5 hours to bet at any sport makes it way too limited in terms of choices.
I played on Betonline. Deposits using cryptocurrency are available there. It seems that you can also deposit using cryptocurrencies on ACR. In my opinion, Betonline is a reliable site, at least, I haven't had any problems with it.
Sorry that the poll is closed. 🙁 I should visit this forum more often. 🙂
That said I would go with video poker. In a perfect world blackjack would have been my choice but I haven't counted a card in at least 25 years, and don't really want to put in the effort to learn it again. (I played Wong Halves doubled) Since I know the odds with poker hands, and can use them to choose which play to make, video poker is going to be my best shot. When in Vegas I play it during breaks in tourneys and while having a drink at the bar, and come out ahead more than not. 🙂
I would choose sports betting 🙂
I think it wouldn't be that difficult to accomplish such a task. A 20% profit in sports betting is absolutely realistic.