All you can do in Vegas Pro is to tinker something which would more or less look close to a real shadow. The best tool available for this imho is the shadow tool of Track Motion which allows to turn the shadow 360° around, move to any position and modify the size, aspect, etc. as desired.

This was entirely made in Vegas Pro (click to enlarge):

For real shadows you would need to use 3D software like HitFilm, but this again would need even your object/subject/charakter must have been created or at least positioned within a 3D space.

Thanks all so far. I "kinda" found a solution, not 100% but close.

I copied the event, put it on top, flip vertical, reposition, brightness to zero and alpha at 50%.

It mirrors and follows the moves nicely, the only problem is that the mirroring is sort of wrong when the legs are not on an equal horizontal axis, creating an "in the air " effect. (see pic)

Marco, I tried the 2D shadow approach, but it does not get my shadows to the front where I need them, and doesn't mirror the object. Good idea with Hitfilm, but right now too much of a hassle. If I find the time before the deadline I'll give it a go. Hitfilm is cool, but IMHO very counter intuitive to manoever, at least compared to Vegas. I really seem to have a hard time with the learning curve there.

@Mindmatter - Oooo I DO like that. 👍

Yeah, looks great (except the shadow of the very left person which is shifted too much away from the subject).

For mirroring the Track Motion 2D shadow you need to use the right-click option. But your solution is even more flexible.

Marco that's really cool! It's the same thing as mine without the hassle of a second track per object. Horizontal mirroring is still flawed but it's much easier to handle. Thanks a lot!

Would be even cooler if one could adjust the angle though.