Pass commandline to wt:
As shown in Option 1, the commandline option can include further parameters for the target shell, with the following working when called from a batch file:
wt wsl.exe ssh -L 3306:localhost:3306 -L 5900:localhost:5900 -L 8001:localhost:8001 user@target.com
I did not find any official online resources explaining why this works, adjusting the suggestions in this answer, so I'm not sure whether this is supposed to work this way or if it's a hidden/unintentional feature that could break in future versions.