Are there any Third-Party Apple Watch apps that render HTML emails and provide push notifications?

Since Gmail as a service does not support push on iOS Mail, I do not get notifications for emails as they come in unless I use a third-party email app. I have used Outlook for iOS for a long time now, and it has worked great. However, I recently got an Apple Watch, and I was disappointed to find that the Watch app for Outlook does not render HTML in emails. The emails are plain text only. From what I have seen so far, the built-in Mail app on Apple Watch does a good job of rendering HTML emails. I have not had any luck finding a third-party app that can do this, though, so that I can get both HTML rendering and push notifications for email. Do any Watch apps that render HTML emails exist, or does Apple not allow third-party email apps to render HTML for some reason?