HTTP/2.0 Server-Side Traffic

Think about HTTP/2 profile like any other profile, let's say severssl profile.

You could have servers doing SSL, but in a failed scenario send people to a static sorry page without SSL.

In that case, before redirecting to that new server, you remove the serverssl profile.

In theory, the same idea could be applied to HTTP/2, so in the iRule/LTM Policy you remove the HTTP/2 profile before sending traffic to the server.

I said in theory because I haven't tested it.

However, this bug proves it should work:

https://cdn.f5.com/product/bugtracker/ID869553.html

The bad news is the bug above, and that I could not find that opiton using LTM Policy.

You could open a ticket with F5 support to see if there is any engineering hotfix for that because it applies to all the latest versions.