I'm not sure how WT operates through Patreon exactly, but I think they essentially pledge to you as if they were an individual Patron, but don't select any tier rewards you may offer . Anyone who's actually enrolled in the program can please correct me.
But anyway, Patreon fees are calculated thusly and depends on where you live.
And then here are Paypal's fees. The fees mostly apply to when you are selling a service, like when someone commissions you. Speaking from my experience via Tapas' transfers. When I go to withdraw money from my revenue balance, let's say for example the balance displays as $103.71, Tapas will send that amount to my Paypal and I will receive $103.71 exactly without any fees taken from my end. This is because Tapas takes the fee hit for paypal transactions and thus doesn't calculate into the display in your revenue balance box. WT may be similar this way? But I can't say for sure since I'm far from reaching the requirements there.