I kept a 6 gallon eclipse with mutiple shrimps in the past. It housed: 1 banded coral shrimp, 1 cleaner shrimp, 2 red blood shrimps, 2 harlequin shrimp, 1 peppermint shrimp, 1 sally lightfoot crab, and 1 hermit crab.
My CBS ate my sally light foot when he molted; my pepermint shrimp died didn't know what killed it, just found it lying on it's side.
All others did well for many many months. But this was in my younger years when I was very green; and nanotank was not out to help me. I lost a lot back in the days trial and error; so I have lots to share.
Please don't do what I did, but know it's doable and the only reason they live is survival, they don't want to get eaten; so they run or move out of the way.
What I did learn is that all critters learned the exact coordinates of the CBS and avoided him like the plaque, then the next top predator was the redblood shrimp followed by the cleaner and then the pepermint.
Larger tanks can house all of these critters but the nanos are asking for trouble, just get a pair of your favorite and watch them become bold and crawl all over your rocks.
Hope this helps out.
Mike