I don't know of any mods, but there is a glitch that you can take advantage of to add extra muscle to created female wrestlers.
In the create your superstar menu, go to body, then body customize, where you choose two body types. For the second of the two body types (i.e. the one on the right) choose Type 20 (the most muscular one), before moving the slider below as far to the right as possible (assuming you want your wrestler to be as muscular as possible).
You will then need to get the first body type (the one on the left) to be Type 21. However, choosing it manually from the menu will not achieve the desired effect. Instead, you need to keep pressing the random button until you get Type 21.
Once that has been done, press accept, and you should have a female wrestler with both body types 20 and 21 combined together as one.