as for WandaVision , as of right now , there are no plans for a second season
as with all the up coming MCU TV shows , their all , as of now , one and done types of series , except for LOKI , thats the only show with a confirmed second season
Marvel keeps everything top secret , so no one knows for sure if any other show will get a second season
but that doesn't mean that the events of those shows won't continue into other shows
consider WandaVision as just Act 1 of a 3 Act show , the events of WandaVision will continue right into Spider-man No Way Home which comes out in Dec , and that will continue into Doctor Strange Multiverse of Madness which comes out next March , so we ain't done with Wanda yet , we'll see her and the Darkhold again , so they wouldn't admit a second season of WandaVision now anyways , because we won't know Wanda's fate till at least next March
and as far as who will be the next Captain America , that question will probably never be answered , in the comics , several ppeople have carried the shield over the years , so I'm sure the same will be with the MCU
as far as Chris Evens coming back to play Captain America , Kevin Feige was on record today saying , Chris Evans will not be coming back as Captain America
in the comics , both Sam Wilson and Bucky have both been Captain America at one time or another , along with another chracter named John Walker
in Falcon and the Winter Soldier , we'll get to see Sam Wilson deal with the acceptation of a black man becoming Caption America , while Bucky deals with his own demons of having his head scrambled so many times , and being a man out of time , just like Steve Rogers was
which then leads us to John Walker , who at some point will end up with the shield , John Walker becomes the character called US Agent , who is basically the government employed version of Captain America , although John Walker has issues of his own , ex military with anger issues , he doesn't have quite the same morals that Steve Rogers had
John Walker is being played by Wyatt Russell , he's the son of Kurt Russell and Goldie Hawn
so..............
for what we know as of now , John Walker / Wyatt Russell is set to become the new Captain America / US Agent
but , this is the MCU , so we knows there's gonna be a twist.................lol