Is there a way to change Display Modes for a disabled Monitor and Display Adapter combination?

Trying to solve an issue with my StarTech 2-port DisplayPort KVM Switch - USB 2.0 - 4K 30Hz, and that last bit, 30Hz is probably my issue.

Unfortunately, I've messed and trying to have two monitors...

1. Work the windows to change my Display Adapter Properties' Display Mode into a 30hz variant.
2. Go to the KVM to see when it finally works.

Monitor 1 goes basically black while Monitor 2 is on. Probably navigable if I memorized everything, but that's a bit tough.

Not even doing this right before turning Monitor 2 on:

start-sleep 5; displayswitch.exe /external

Or /internal, fixes things.

So is there a way to change the Display Adapter Properties' Display Mode for Monitor 2, without having Monitor 2 be on? Without installing any third-party programs?

A.k.a via Device Manager or PowerShell?