Why is it “Who be ye?” and not “Who are ye?” in archaic forms of English?

When I was looking for “ye” in a dictionary, I stumbled upon the phrase “Who be ye?”. But why is it “Who be ye?” and not “Who are ye?”? The modern equivalent of “ye” would be “you”, wouldn’t it? “Who be you?” would be considered incorrect, whilst “Who are you?” would be perfectly fine.

There were several ways of conjugating to be in Early Modern English.

I am; thou art; he is; we are; ye are; they are;

I be; thou beest; he is; we be; ye be; they be.

I believe a combination of these was also used by some sources: namely, am/art/is in the singular and be in the plural.

"Who be ye?" is simply using the alternate form. But "Who are ye?" would have been grammatical as well, then, at least in some regions of England. Shakespeare generally used "Who are you?" and the King James Bible generally used "Who are ye?"

The OED mentions this in its discussion of Early Modern English grammar.