at this time it is very rare to stop by an airdrop event that produces high ROI, moreover POS-based coins are very rarely found using the airdrop concept. If you are looking for airdrop but limited to POS algorithm coins I think it is very difficult, but if you want airdrop, there are many places that can be visited by you, indeed bounty projects are few but the airdrop program is more abundant this year, it proves to be a lot of people promoting links on my social media homepage. You should be able to search for it in the browser. But one thing must be remembered from the many airdrops, maybe no more than 5 airdrops can be money.