Note i am not a Mod nor an Admin-
I would encourage against it myself, quite a few people want to do it as it's "cool" and all that stuff not to mention I feel like its kinda cliche.
It is allowed however as far as I know, I've fought one or two dual wielders myself.
I would stress you to take your time and customize something for yourself with that you can truly feel happy with. I would also say that if you HAVE to dual wield go with something unorthodox like Katars or something.
But take your time you dont get shikai til rank 2, you have plenty of time.
-Not a Mod/Admin-