As I think others said here, at this point I would boot in safe mode and see if if the problem persists. If it resolves in safe mode you made need to do a clean boot with your Laptop as something is wrong.
Make sure you have a system restore created first before doing a clean boot, the clean boot will basically run win 11 on a minimal set of drivers, if it works then try a normal boot, if the problem persists you have some kind of program mucking up the works probably.
Another thing to try is changing policies for the USD HDD for better performance.
Seems unlikely a specific HDD issue if both are doing the same thing but it could be both are bad.
Do you know how long it takes to format a 6 TB hard drive over a USB connection?