When picking up a body (atr the very beginning of the game) and later dropping it, NOMAD is holstering the weapon during the drop, but no re-equiooing it after.
When then coming to use the weapon again she is drawing the weapon.
Regardless, the way she is holding her hand is looking very strange (like playing cowboy as a child without having a toy gun).
Bets would really be to have the opportunity to holster and draw the weapon on key press.