As Dortania's OpenCore Post Install guide states:
...macOS will instant wake if either USB or power states change while sleeping. To fix this we need to reroute the GPRW/UPRW/LANC calls to a new SSDT...
The best way to check if you're having wake issues is running this command and analyzing the output:
pmset -g log | grep -e "Sleep.*due to" -e "Wake.*due to"
In my case only GPRW was needed, so I added: