I’m not sure all of those will will work. I don’t know when you’re planning to go though.
It’s unlikely the security check on the path from Contemporary to Mk will be open and let you through until pretty much when they open the gates.
You could hop out at the Boardwalk gate if they won’t let you in, so that should be OK. Don’t expect the Epcot monorail to be running before 2021 and possibly Easter.
For DHS the boats aren’t running and again, I wouldn’t expect them to restart before either park hopping is permitted or until BWI &/or BC open, which could be next summer. So be prepared to walk from the Boardwalk to DHS.
And for AK currently buses aren’t only arriving until about 30 minutes before park opening. And neither is the parking lot so you’d have to hop out of the Uber before then and walk in if you are permitted to, which I doubt.
I’ve seen reports of cars being turned back from parking lots, so not even allowed to wait in a line to get in. Some just then park up on verges unless the police turn them away.