These type of custom tweaks can be done by using the MainWP Custom Dashboard Extension. If you have some JS coding experience, I believe that this could be done. If this is not something you would like to try, please let me now and I will move this topic to feature suggestions section.
@techboy To expand on @bogdan’s response - you will definitely need to add some custom JS in order to pull this one off as it’s simply not in the core code of MainWP.
We use the DataTables.js library which is highly expandable.
Check this thread out here in order to get a grasp of what you are trying to achieve. You will then be able to use the MainWP Custom Dashboard Extension to add the JS you need without having to edit core MainWP code.
Again if this is just out of your reach then we can set this ticket as a feature request.