Unsteady Platform Penalty

So the Steady Shot weapon trick is the sole mention of an “unsteady platform” penalty in the core book. There’s no mention of the actual penalty anywhere. This leads me to believe it is a carry over from Legends if Arcanis. Since I don’t own that game, can anyone help me out and tell me what that penalty is? Is it a minor or major penalty in terms of that game? Does it just apply to firearms, all ranged attacks, or all attack rolls?

If I were to crib it from a similar penalty in Savage Worlds, I’d rule that it applies a -2d penalty to all Ranged Attacks. Sound about right?

With that, I’m considering a couple of options and repercussions:
A) if the penalty is non-existent, than the Steady Shot trick is meaningless and firearms need a new basic trick.
B) if the penalty is recognized, is it worth the creation of a talent (basic or greater, I think) to negate? In which case, steady shot probably needs a replacement or at least some modification. I think this would be valid if the penalty applies to all ranged attacks, or attacks in general.
C) to keep the trick valid, offer more avenues for players to learn that trick with different weapons.

Thoughts?
Tom