@Tony I bought the RE505X extender thinking that LAN meshing was possible, I'm going to return it since I literally have no use for it without that functionallity, I have both an Archer C7 and an Archer AX6000, I first bought the AX6000 but found that one part of my house had some issues with the signal. I prevously had Asus routers that allowed meshing with each other, so I bought an Archer C7 because it said that it was one mesh compatible, I tought that tp-link was on par but I was mistaken. Then I bought the RE505X thinking that it might solve my problem but then again I was mistaken, I sincerely don't understand how their product for range extension doesn't have this functionallity. I'm just going to recommend Asus from now on for people that want flexible meshing, It sucks since my AX6000 had been working great.
TLDR: Buy Asus if you want LAN meshing with your big router.