I only checked Jupiter, and from their blog post it seems they just recently launched the trailing stop feature? It was posted on July this year iirc. I guess we'll see more DEXes develop similar tools in the near future. I can't imagine using another platform that offers nothing like that when the market behaves erratically, especially when it's not that hard to use. The alternative is to run your own bot connected with the API of the DEX you choose I guess, especially if you want more complex indicators to decide when and how much you'll sell. CMIIW.
Yes, Jupiter only integrated it recently and it's quite helpful. More DEXes to implement unless they don't love money and don't like their customers. If you want complex strategy, it will be through bot, it will watch oracle price > check the dex quote > execute. The strategy engine is usually built around oracle price even though there can be price different with the real dex quote. I prefer dex provided features over bot implementation because it's free, more accurate, and faster because they have access to internal tooling. Writing a bot to watch oracle and constantly quote dex price is a pain from my personal experience, but AI can do this in just 5 minutes if you don't want to write it yourself, just make sure you tested the security first and testing it on testnet.