Anyone can help me? how can i put the shotgun with the engi animation?

[[ΖмBя.™] NordestinoRico]

 

[Tiftid]

You could try doing this:

The relevant attachment for the Engineer would be "effect_hand_R".
In Hammer, the outputs for that would look like this:
(note that both models should be prop_dynamic)

If this is about SFM, attachment points are still what you need, but I don't remember how to lock models to attachment points in that program.