Object that follows mouse position. How to properly do it with BP?

I think this is what you are looking for:

All you need to do is change the break vectors to the direction you are facing (X,Y,Z) I don’t think +/- matter

Here is a text you you can copy-paste into the BP:
[Paste][2]

Also, you can subtract your first break vector float you chose by an amount if you want to use less of the viewport to move the mesh (by default it will use the viewport bounds for the movable units, so if the viewport is1920, the mesh will move -960 to 960 units)