More than likely stupid questionFollow

im pretty sure this is a stupid question, but i gotta ask anyway.

is there anyway to train so we can use main hand weapons in our off-hand? one of my friends had heard something like that but i'm not sure if it was just some moron talking somewhere, and if it really is true, where would i be able to find the trainer for it.

Main hand only goes in your main hand, one hand can be used in either hand, offhand can only be used in your offhand. The only training needed is dual wield afaik