Parkin has shown very slick and solid fundamentals so on paper he should be able to style on Usman BUT dealing with a guy as physical as Usman in reality is a challenge since he can just power through techniques. Most HW's aren't used to being physically overpowered so there's a small chance Parkin freezes.
I expect the fight to start slow with lots of early feints but as Parkin gets his reads, timing and range I think his combinations and distance management will be enough to take over the fight with authority Usman potshots well but pretty low level setups behind decent timing. Parkin trains with Aspinall so I doubt athleticism will shut his style down.
This fights a great test to see if Parkin's a legit HW prospect or if he's way too safe for his own good to go for the kill against a flawed challenge.