I love to play as an argonian, and it's the reason why I never play a Vampire Lord, because the humanoid appereance of the vanilla model is too much of an immersive breaker to me.
So with Blender I had some fun working around with some models I found, combined them and retextured them. I posted some pic exemples I made for a male type model of the two beast races !
I have absolutly no Idea on how to incorporate those in the game (if it's even possible at all), and I don't think I'll have the time to maintain a propper mod for users.
So, if someone feels like making one and want to use these as a base mesh model, just tell me and I'll share it.
It's really rough and messy but maybe It can help.