May I know how can I use SF Symbols beta to create custom icon?

I am using "checkmark.circle.fill"

I wish to have a blue filled circle with the checkmark being solid black.

For the blue filled circle, I can choose the tinted color as blue.

But, the default SF Symbols "checkmark.circle.fill", its checkmark is transparent.

It looks as follow

So, I try to use "SF Symbols beta", to create custom icon. During editing, the thing seems like what I want

1. Blue filled circle
2. Solid black color for checkmark

Then, I use "Export Symbol...", using Template Version 2.0 (XCode cannot recognise Template Version 3.0)

It seems like the checkmark fall back to transparent color. When I import it to XCode

It seems like the "solid black color" on the checkmark is gone. When I use this custom icon in my app, it gave same result as "checkmark.circle.fill" (the checkmark still remain as transparent)

Doesn't anyone know how to resolve this issue? Thanks.