Gotcha. Your board has:
a) onboard SATA ports to which you can connect 8 SATA drives
and b) an onboard LSI 3008, which can handle 8 drives with an 2x (SFF-8643 to 4xSAS/SATA cable)
You probably don't need this 3ware controller at all.
If you wanted to unify all the drives on 1 controller, you...
You can add with Powershell.
Figure out what all the disk numbers are (In Computer Management > Disk Management) and issue a bunch of these commands? Or try Get-Disk without any integer after it to do all drives; I think it'll error on drives that aren't offline anyway, so the host drives...
I've not used the 9362. Maybe see https://forums.servethehome.com/index.php?threads/any-experience-with-the-nec-9362-8i.23778/ ?
9361: MegaRAID 93xx 12Gb/s SAS Storage Adapter Drive Compatibility Report Selection Guide shows 512/512e/4K drives as supported.
Yes, mine is an actual HBA in IT mode. LSI3008.
I believe I am aware of the requirements to do this conversion; I've done this successfully in the past, but it is not working with these Seagate/IBM SSDs.