I can't find any mention of this on the roadmap so I hope it's okay to post about it here, but GCC tenants are still unable to utilize approval workflows, they just fail out immediately. Microsoft documentation at https://docs.microsoft.com/en-us/power-automate/us-govt currently states that this isn't supported in GCC right now but there's no word of when it might be. Overall I find if it's not on the roadmap for us, it might be getting overlooked.
I can work around this some by using "Send email with options" but what our users really want/need is the core approval functionality. While we're also facing restrictions on cooler things like adaptive cards, bots, and accessing the graph API, the approval feature is a basic thing. I know there's red tape, but I fear how far behind we could end up.