Good news. Yes, Photo Mechanic® 6 is a 64-bit program that is fully compatible with macOS Catalina.
Prior versions of Photo Mechanic, such as Photo Mechanic 5, do not run in Catalina. If you are upgrading macOS on your computer, be sure to deactivate your Photo Mechanic license on that device before upgrading.
If you have already upgraded to Catalina and can no longer open Photo Mechanic 5, please contact support for assistance in deactivating that license.