I'm also kind of new, but I'll try and help in whatever way I can. If the Beowulf in question is trying to be super mobile and hit you with those jumping overheads, you've got a great anti air grab. Also, range can be a problem, but Merry-Go-Rilla is a really great way to catch them off guard, especially since the range on it is pretty nice. Don't totally abuse your grabs because that can get pretty predicable, plus, a whiffed grab can mean serious pain for Bella. Don't be afraid to play a neutral game, if you blindly pressure you're gonna get grabbed and that can be especially painful when dealing with Beowulf. This is also sort of general, but, more than anything else be patient. Bella's kind of like Hugo from SF in that way. You can apply pressure when you need to and grab when they least expect it but if you get salty and start mashing or just run in without a plan it's real likely you'll get bopped. I wish you best of luck against Beowulf and I hoped this helped.