For crypto, I use BIGGICO, I think that this is the best cryptocurrency affiliate network in a market. But depending on the specific purpose, there are many types. I also use several of them to monetize ads on my website and blog. In general, most of the CPA Networks that I use can be found here https://www.affiliate-programs.biz/category/cpa-networks/. Get to know and maybe some of the above will suit your needs. The list there is quite large. I also use CPA to monetize Arabic traffic, since there are many people interested in cryptocurrency.