I have one gmail account made last year that has a "Sent Messages" label. And another gmail account without it.
I think this was gmail's default, but for some reason it was erased on the newer account, or gmail stopped having that label somewhere. I tried finding the logic / rules for it, but there's nothing I can uncover to mimic it. Does anyone know the formula for it? I don't want it to label messages that are replies in my inbox, just the ones in my sent inbox.
I've looked through a few answers, and came up that I need the is:sent rule, but I don't know how to incorporate advanced parameters into a label filter.