You have already published it in one Community. I think that is enough. Don't publish the same story in another Community. You can't publish the same story more than once.

There is a feature named "Cross Publish" to another community, but you have to first look at the other community and see whether they accept cross publishing. You can't be rewarded twice. So you would have to decline rewards when you do this.

The best thing is to decide before you publish which Community you think fits your writing. You can always utilize tags for the communities.