Easier way to add worktrees and check out branches

Suppose I want to play with certain branch in the repo of which I already have a worktree on another  branch.

I try Repository->Add worktree  - oops, it tells me that I don't have that as a local branch...

Can this Just Work, please? All I want is get me a new working directory for certan branch, presto.

If this takes some actions under the hood, please do this for me.

* I cannot do check out on this branch, because this will stomp on my current working directory (where files are already open in my IDE ...)

* I don't want to go all the way from Repository->Clone.... enter the repo URL, then the branch....