If there is anyway to make this happen it would be a lot easier to scam people's posts and see if they are abusing merit
So you want to be able to see how much merit someone earned for a post? But that wouldn't allow you to determine if the poster is abusing merit, because you'd be seeing the merit received for such posts.
It think your best bet is to look at merit sent for each target "abuser" and go into each post one by one or look for single members that are receiving a lot of merit from the target "abuser".