Alright, let's take a look.
Big Nep here is most likely to start off with just simple, basic attacks using her twin swords, both of which Goku can dodge.
When she finds out that that method isn't working, she'll most likely resort to try limiting Goku in some shape or form, which is where she can try Paralysis. But, the catch is, in order to paralyse Goku, she'll need to hit him.
Her best bet is to create a Giant Pudding to try and limit Goku's field of movement by quickly trying to sufficate him, but Goku can just either kamehameha the pudding away or just simply use Instant Transmission.
Big Nep could try sealing and gaining Goku's powers through her Nep-Note, but even if Goku was sealed, he could break out of it, as Arfoire once did as she was strong enough to do so (after she gained energy, of course). But, even then, that's assuming that Goku doesn't simply use Instant Transmission as she is trying to seal him to get behind her, failing the seal.
Big Nep can't really do much against Goku here, though her increased defence will draw out the fight quite a bit.
This is such a tough thread, with two of my really liked characters fighting against each other... But I'll have to vote for Goku here.