Bean does have this feature, but with caveats. At the moment the smoothest way I’ve found to experience a multi-community is by grouping them in a list on Mastodon.

Yea the current Bean implementation just stacks 10 posts from each community on top of one another. The posts are “grouped” by community, rather than being thrown into one big group and then sorted by hot, new, etc. I’m sure the latter option is more complex, I’m just hoping someone can eventually do this more like how a multi Reddit worked.