I heard that sword is a bit bad due to how flurry and onslaught works and 1 miss could break your fun. Better check your IRL luck first, who know how many times you'll encounter that 5% on crucial times
As for shotgun, I think it's better if you main shotgun and use sword as alt, since shotty's perk is damn good. You could probably make due with Leading Shot only, since shotty's accuracy is pretty bad
I'd recommend just straight up throwing + grenade tbh. 50 throwing w/ three-pointer + grenadier is enough to gives some burst damage every now and then, and it's accurate enough for short throw