He would use the redesign because that's the one that's canon

The designs which appeared in comics are canon.

OK but as I said the first design is used. Do you think that Kuro should tell us in the comic how he go to the second design or how the omitrix change its color (between first and second design the omitrix has different color)? For example an update of omitrix etc. Don't forget that he has redesign and other aliens that he already used them in comic. Like :

These are just commissioned by 5YL community because they want to see some aliens in kuro's current art style.

A OK is anyone of them (chromastones) non canon?

It is just redraw of chromastone, they are same.

Not like an alien, like design for example is second design of chromastone non canon as a transformation of Ben 10? I say that if Ben transform to chromastone from which design will has the appearance?

They are canon, like, it depends on kuro's current art style, if chromastone appeared in chapter 10, he would have his new design.

The canon reason chromastone’s 5YL design has changed is the same reason that Chromastone had 2 designs in Omniverse. What ever that reason is.

Kuro is only Updating the Art work from his Old artstyle to his New artstyle, you can clearly see that one is an improvement on the other,