A software that I've used, which is also free, is Fire Alpaca. I've known people to do any editing in it's sister software Medibang Paint Pro for most coloring, lines and other details. Both of these have been my go to.
As for other animation programs I know there's Pencil 2D, an open source animation software also free. Krita has an animation feature, it's also free but I'm not sure if the animation feature is out of beta (i've also heard it works better on mac than windows).
If you're in for spending money on animation software I hear Adobe animate is good but I've also heard some positive reviews of Toon Boom and TV Paint Development.
I'm also aware of Clip Studio Paint having added an animation feature somewhat recently but no experience on it functions.
I'm certain there are some other good ones especially a good bundle of freebies but those are the only ones I can remember off the top of my head
Hope it helps! 