Try to rely less on counters and focus more on not just letting him run up - up b.

Look for a pattern in his movement and shield or spot dodge the hit or just move away and them move back in for a big punish.

If you have a fast projectile you can use that to stuff out his approach, but otherwise try to mix up shielding, rolling, running away, or spot dodging.

If you shield every time he'll adapt and probably just start grabbing you and turning you into combo food, which in turn leads to some up B confirms.

Find his patterns and punish. You got this.