Fork a repo, simple way to pull merge requests for original into fork?

The KiCad footprints repository has currently over 400 open merge requests:

I created a fork of the repo and, besides my own additions, want to add as many of the origin merge requests as viable to create an easier way to review the parts (in KiCad, not review patches).

Is there a way to merge parent merge requests in my fork in bulk or with one or two clicks per request?

Digging through the merge requests system I didn’t come across any way of adopting any. Mailing over 400 people to ask them to re-do their efforts with a new merge request to me isn’t viable either, a fair number of these have been abandoned when they received no attention for years.