A bit of a hassle, but you can revert the VM tools v10 back to vmx-9 which is editable via the vSphere client (no need for vCenter):
1) Open up a SSH connection to the host.
2) Go to the folder for the VM.
3) Edit the .vmx file with vi, i.e. vi MyVM.vmx.
4) Change virtualHW.version = "10" to virtualHW.version = "9".
5) Remove the VM from the inventory by right clicking it -> Remove from inventory. (Do not delete from disk!)
6) Open up the datastore browser (right click the datastore -> browse) and go to the folder for the VM.
7) Right click the .vmx file and choose add to directory.
😎 You can now edit the settings via the vSphere client and you do not need vCenter at this point.
Hope this helps,