We can't discuss a Mac VM here - it is a violation of Apple's licensing to run their OS on non-Apple hardware.  VMware could get into legal trouble.  Also, the only way of even attempting to run MacOS on Workstation is to illegally modify it... so you've come to a vendor's site admitting you hacked their software and are asking for help with it...!

I'm not asking for help on MacOS. I'm asking why my Windows workstation isn't appearing in the list. 

Perhaps it has something to do with the modifications you made to Workstation?

Perhaps it has something to do with the encryption required for Win 11 VMs?

Ahh, it's probably the encryption for Windows. Are there workarounds?

it seems to only show vms in the "My Computer" root folder. Any VMs in a subfolder wont show up for some reason.

Autostart feature does not support Encrypted VM. 

Probably, Your Windows 11 VM is encrypted. That's why not showing in Autostart.

Thanks,
Sajesh

I disabled TPM; is there a way to unencrypt?

Are you sure the issue is related to encryption, etc? You can check VM encryption by right clicking on the VM itself, then entering Settings > Advanced > Access Control.

I came across a very similar issue today, but the problem was that the problem VMs were stored in a subdirectory of my primary VM folder. It seems the autostart feature only works out of the basedir.

It is encrypted - that's the problem and won't give me the option b/c of TPM. I removed TPM but still don't have the decrypt option (Windows 11).

Thoughts?

Windows 11 VM as a default -- Encrypted and TPM added. 
So, to reflect in Autostart for any VM - The VM should be unencrypted 

Steps - Go to VM -->Settings --> Options --> Access Control --> Remove Encryption (If this button is disabled still, a message appears, if any snapshot exists, remove it)