Amazingly, this fixed it for me!
Go to the App Store Connect and select the team you don't have access to in Xcode.
Go to the "Users and Access".
Find yourself and click/tap your own name/user.
Change the "Preferred Currency" to anything else (and back, if desired).
Press "Save".
Logout/Login into Xcode and you should be able to see the team now in the list.
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PadraigOC
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I didn't expect it to, but changing the preferred currency worked!
I filed FB9860514 for this
I'm seeing the same thing. Developer role on a new team, access to certs checkbox is on, but the team doesn't show up in Xcode or developer.apple.com.