Are Flutter 2.2.3 and Android Studio Arctic Fox latest stable version (2020.3.1 patch1) optimized for Windows 11?
Is installing these two on the preview version of Windows 11 a problem?
On the Android Studio Website the following Windows operating systems are listed as System requirements:
64-bit Microsoft® Windows® 8/10
So technically this would mean you're outside of the system requirements and Android Studio is likely not optimized for Windows 11. Dart has pretty much the same situation, listing only Windows 10 as supported.
From my personal experience, everything I've used in Windows 11 has worked the exact same way as it would have in 10, but there's always the possibility some issues will arise with unsupported software so staying within supported versions is always the better option if you don't want to deal with problems.
In short: It's not supported, you may run into issues, use it at your own risk. If you want to be safe, use it on Windows 10 until Windows 11 starts being supported by both tools and upgrade then.