Hey ring,
I know this isnt the answer but I am using the ShortPixel Adaptive Image plugin on all my wordpress sites and they are being served as webp. AppSumo had a great deal for them recently and I purchased a couple of codes for it but when I checked today, the deal had expired. I believe they have a free version but not sure if you would be able to auto use their CDN.
Funny, that's exactly why I'm asking for webp support. I bought this great deal from AppSumo as well, and although I've marked in its settings to use webp, I'm still getting JPGs. I thought it had to do with my setup.
But coming to think about it, as they're being served from their CDN, why would I still get JPGs? Weird...
But anyway, I host other sites for my clients, and I would like to support WebP for them.