Graphic glitch using Metal API

I’m on a 2016 Macbook Pro 13" i5. Big Sur 11.2.3. I just recently installed SC2 (5.0.7.84643) on an external NVMe. Running Window (fullscreen), 1152x720, default medium setting. I found that if I run it under Metal, the graphic will glitch/flicker when there’s a large amount of objects on screen (I was playing coop and I had reached full pop cap w/ Reynor).

I thought it was because I’m running it on external so I tried playing another game, Company of Heroes 2 but I had not have any problem with that.

I then switched the render API to OpenGL and I played a couple coop and I haven’t been able to reproduce the problem under OpenGL.

Has anyone experienced this problem?