About the conflict with shanks, i can assume some other situation.
I assumed Usopp will meet his father at some island, before the rest of crew meet each other, they get into conflict cause Usopp is incredible mad about his father, letting his mother die, never returned etc.. So Usopp will attack his father, Shanks crew will interfere, maybe even shanks attack Usopp, till Luffy blocks him. Then there will be the conflict, will he order Usopp to calm down and forgive his father to let the mother die, or will he stick to Usopp and so go against Yasopp/Shanks Crew.
I assumed Usopp will meet his father at some island, before the rest of crew meet each other, they get into conflict cause Usopp is incredible mad about his father, letting his mother die, never returned etc.. So Usopp will attack his father, Shanks crew will interfere, maybe even shanks attack Usopp, till Luffy blocks him. Then there will be the conflict, will he order Usopp to calm down and forgive his father to let the mother die, or will he stick to Usopp and so go against Yasopp/Shanks Crew.
I don’t think anyone will intervene though.