My legs are fine for the time being, I do them every so often but not weekly.
I can handle tricep/back/chest in one session. I have quite a few compound exercises so I can hit 2/3 muscles at the same time which helps.
I don't mean to be offensive, but there's so much wrong with your outlook it's not even funny.
You should work legs if you want to train anything else, it really is vital to building a good upper body. You won't grow anywhere near as much as you are able to without training legs at the same time.
If you're training properly then there's no way you'll be able to do chest and back in the same session without hindering your progress. They're very big muscle groups, it makes sense to space them out like you would legs from chest or back, for example.