This is a follow-on to Can you cast spells with a Somatic component if you're holding a two-handed weapon?
So, I have a spell, say Sanctuary, that is cast as a bonus action, yet requires Verbal and Somatic (and in this case Material, but that is taken care of by my character's holy symbol) components to cast. Can my character take their off hand off their two-handed weapon (light crossbow) to cast this spell as the bonus action, then regrip the weapon with both hands in order to use it as the turn's regular action? Or do they lose their regular action in order to regrip the weapon?