WebP support for email

I began with this thread in WordPress Github Issue:
https://github.com/WordPress/performance/issues/74

AppleMail and Gmail won't have any issue. Outlook still struggled at the moment, at least on the app side.

Is that something can be done by using Microsoft Outlook Tag to wrap the fallback jpg file while other webmails or modern email client app can benefit from what WebP offered? For instance:

<!--[if !mso]>
<img src="___.webp" alt="" />
<![endif]-->
<!--[if lte mso 16]>
<img src="___.jpg" alt="" />
<![endif]-->

Can you share if any tactic that works for you?