Action points aren't designed to have a scale. they are just a point to spawn or anchor something from or to.. You could use a place-holder image or bone instead, theoretically. depending on what runtime API you're using.
This is definitely the correct place to ask questions
First of all - If you want to know a specific location from the animation, you should probably use action points.
At the moment, the point transforms are not being converted into MonoGame coordinates (since I didn't know of a use case for this) but your question made me realise there should at least be a generic method that converts transforms from Spriter to MonoGame. I'll implement that asap.
If you need such a functionality in the meantime, you can take a look at the MonogameDebugAnimator. It is piggybacking on the functionality of transforming sprite coordinates to draw action points. If you run the example project and go to the 4th spriter animation ("GreyGuyPlus/player_006") you'll be able to see that in action.