Like Dapoolp said, there are ways to tell if you have sneak attack, especially with how many ways Larian gives advantage (btw, NOT getting into that debate since I don't have an opinion on it). However, I also am not sure why sneak attack needs to be a dedicated skill button and not applied automatically. Perhaps it's to avoid having sneak attack more than once for dual wielders/haste without overly complicating the coding? Unfortunately, I find it more common that I forget to click the button...
