I just checked because I couldn’t believe it, but you’re right, they charge 0.20chf for every incoming payment!? 
I don’t know much about CSX. It just gets mentioned every time free banking products are discussed.
Off the bat, I’d probably favor Neon. I already use them for international credit card payments.
I feel they’ve had a different main focus and pushed different core products so far:
Yuh: primarily a multi-currency investment app. Current account and bank card are an ancillary product.
Neon: primarily a current account and payment app. Investment/lending products are ancillary offers.
Not saying their respective ancillary features are necessarily bad or worse. Especially the technical features and implementation of the card - though Neon will replace their cards and change to a different processor soon. But Neon is clearly more geared towards payments. And the 0% FX is a great advantage if you don‘t have or want to use a foreign payment card (such as Revolut).