I'm going to update the CONTRIBUTING doc to cover this question. Updating multiple plugins at once isn't something we'd like to encourage; mostly because it requires a super clean commit history in the feature branch, but also because multiple plugin updates are harder for contributors to review, and we've got a lot of folks that only tend to one or two plugins here. To make matters more murky, it looks like the typescript dependency is at the root, so that makes things nice and uniform but also tricky.

For the sake of expediency for this effort, I'd say tackle one at a time, and add the updated typescript dependency to each plugin being worked on. (We can do a follow up commit later to remove this deps if needs be). I do also want to raise awareness in this issue that we have a lot of plugins that we haven't been able to get around to converting to TS, and that's likely more important than updating the TS version, but it's hard to say for certain because one could argue that it'd be easier to do on an updated version of TS.

The individual plugins are using TypeScript 4 now. Should we remove the TypeScript version from the base package.json or should we set the base version to version 4 and remove the version from the sub-packages?

I'd update the base. It'll be a while before we have to do another major version bump of that.

With all of the PRs for this update merged, we should be good to close this.