Primo geovishap doesn't have any specific elemental resistance, outside of geo, and a decent physical resistance. So whatever elements you use is pretty irrelevant. Biggest thing is taking a shielder to block its big aoe. You can get far a away from it to avoid it without a shield, but that would likely mean you're using ranged attacks on it to start. Nowadays I just kind of brute force it at close range while dodging its tail swipe.