Simultaneous branches in workflows

I would love a way to have multiple branches that run simultaneously (or one after the other) but to make sure all branches run, even if one step fails. I was excited when multi-branch came out, until I realised it was only to run the first condition. Ideally, I am looking for a multi-branch option that runs all branches. I specifically use workflows to connect multiple boards and update items with new information, where mirror columns can’t be used because of permissions and data sharing. If multiple boards are connected in one branch, sometimes the workflow will fail half way down the branch because it can’t find an item in one board, but doesn’t continue to work through the rest of the branch.