Merge multiple merge requests together

Hi community,
In my project I have two repositories which are heavily dependend on eachother.
There are situations where open merge requests of both repositories need to be merged at the same time to keep the application functional (changes from repo1 depend on changes from repo2 and vice versa).

Do you know of a mechanic to make this happen?
Maybe a clever way to design your pipeline?

I saw the gitlab premium feature “merge request dependencies”, but this is based on the idea that only a one way dependency exists.

The merge train feature also does not ensure that all MRs are merged (as far as I understood, when the Pipeline of a single MR fails it is just ignored)

I hope you guys have some ideas for me :slight_smile: