Mitsubishi has released version 1.085P with support for Windows 11. As of today (May 5, 2022) you should be able to log into the Software Portal at http://us.mitsubishielectric.com/fa/en and download version 1.085P.
If you haven't registered your software, you will need to register it first. If it's already registered and more than a year old, reach out to Gibson Engineering to purchase a Software Maintenance Agreement which will give you 1 year of updates.
*GX Works3 is used to program all iQ-F and iQ-R series CPUs such as the FX5U, FX5UC, FX5UJ, R04CPU etc processors. Compatibility for Windows 11 and older processors has not been announced yet.