Blocking crossposts, suggested subs?

Two parts:

Is there a way to block crossposts from showing up as a user? If you're in, for example, two subs about a related subject, the same content just gets posted from one to the other almost constantly, and it's frustrating to have to see everything twice, or manually hide them.

Second: In the 'explore' section, if you block a sub from being suggested in your home feed, is there a way to extend this so 2/3 of the explore area isn't the same few things that you don't want to see, endlessly?