Is that this water move too sturdy for my shrimp and a future betta?

You may consider an air filter for a 5g shrimp tank. I have a DIY coarse air filter and the shrimp graze on it all day and the shrimplets also live and hide in it until they are old enough.

Not sure if your shrimp will be safe with a betta in there. I had 3 bettas in a community tank but they were always female and I got them when they were small so they grew up with the other fish and shrimp.

One time I connected a 10g to my community tank with a bridge. My betta moved into the 10g and killed anything else that wandered into it even though there was plenty of hiding spaces in it.