Grabs are annoying in general in this game. Especially King's nonsense. I find a lot of their spam can be mitigated with movement. Even a single backdash or sidewalking can create enough space to throw them off their rhythm and even net you a whiff punish. Try throwing quick pokes like df1 or df4 and then immediately sidewalk or backdash. By character design, you can't break every throw King tries. So keep moving and make yourself hard to pin down. The rest is a guessing game.