In theory I'm almost looking for something like importing the file and scaling all distances with a factor X.
I'm using the scene within Unity where I actually can scale on import. The problem is that I really need to have the original Blender file in the right dimensions, because otherwise I will be counteracting when I use this model as a reference in other Blender files etc.
What is the easiest way to achieve this?
The first thing that comes to my mind is selecting your character in Blender, scaling to the appropriate size and then press CTRL+A to and select "Scale" in the menu called Apply that pops up, that basically is setting the scale property in the Transform menu (see pic below) to 1 again, making the new scale the default for your model, then if you import your model again it should have the desired scale. Make sure to scale the rig too of course and apply the scale for that too, but if you did eveything right they should scale together automatically.
Remember also you should do this process everytime before importing your model into a game engine.
