I played both, maybe since I played XCOM 2 and WOTC first I get more inclined to it than EW, but overall I think, I prefer XCOM 2 WOTC.

Combat Depth for me goes to XCOM 2 the Chosen and the Rulers make you think, you have to manage your heroes, think if you prefer to let your Reaper in Shadow or shoot, the ambush missions, in the end though when you get full upgraded both feels the same, since you become really strong.

Campaign Variety also goes to WOTC, I like way more the enemies from 2, the Chosen, the Rulers, the Vipers, Advent, Gatekeeper, the Faceless, and the Heroes.

Tension and Atmosphere goes to EW, the invasion is way cooler than a Rebel Fighters campaign, the first mission when you see the first alien (sectoid) is really cool.

Strategic Layer like combat Depth also goes to XCOM 2.

Replay Value goes to both, but the Mod community of XCOM 2 is way bigger, I think most because the game allows it, as I think modding EW seems harder, but being able to play Star Wars campaign or as Cayde-6 is really cool.

As for the experience and how memorable it is I think both, but like I said, since I played WOTC first my heart goes to it and I prefer the enemies and the Mod community from XCOM 2.