They still have different pronunciations. "VIH-sem" and "VEH-sem"
vinni (to take): viszem, viszed, viszi, visszük, visszitek, viszik
venni (to buy):veszem, veszed, veszi, vesszük, vesszitek, veszik
There's also "VAY-shem"!
vésni (to lose): vésem, vésed, vési, véssük, vésitek, vésik
You are correct. Who, generally, is treated as singular, even when it "makes sense" or "is meant" to be multiple people.
So who are is grammatically correct, but is unnatural. It is only natural when the number of people referred to by who is explicitly more than one (by grammar or plural noun, not implicitly). Ex. Who is on the basketball team? vs Who are the people going to the game?
This also leads to a weird situation where you may switch to who are based on another sentence. Lots of people are buying cars and trucks. Who are buying the cars? The people who aren't buying the trucks. In this example, the previously odd-sounding Who are buying the cars? should suddenly sound OK.
I just had a look to see if Hungarian has a verb conjugation site like French. I don't know how accurate it is but it agrees with me on this one https://www.verbix.com/webverbix/go.php?T1=vesz&Submit=Go&D1=121&H1=221