2070S is sightly faster but you have to see it the difference of price/perfomance is worth. I was in the same situation than you, 2560x1080, 5700XT/2070S, and I was about to buy the 5700XT but here it is selling at 500€ while 2070S is selling at 540€, so finally I bought the 2070S.
Both cards will run fine, for example in Gears 5 both have the same perfomance, in Battlefield V is better the 5700XT and in Destiny is better the 2070S, so, I think that it mostly will depend of the prices of both cards.