Link will be able to put up a better fight than you may have guessed. His Skyward Slash serves as a decent projectile with a lot of attack power and he can also rely on his Light Arrows if need be. Link’s decisive slashes would certainly hurt Unicron, but the robot can simply spam his energy blasts from afar. It will be very difficult for Link to win an aerial battle so I’m going to have to say that he narrowly loses this fight. Unicron has tipped the scales in his favor here. Unicron wins.
DReager1.com 
OK let’s do the powerscaling here. WEAKEST AVATAR of Unicron is still like 600 feet high. Smashed huge boulders like it’s nothing. Armor so impenetrable that the flipping Optimus prime’s guns did NOTHING.
Strongest avatar? OK F*** SATURN-SIZED BOI JUST CRUSHES ALL OF HYRULE LIKE A WATER BALLOON. XEELEE STOMP!!!
TRUE FORM? OK, dis boi just ate the entire zelda universe without giving two s**ts.
I think you overestimate Link’s abilities. He’s not as strong as he is in the Smash Bros games all the way all the time. I agree with the consensus that Unicron would defeat him and end his universe as he knows it.
i had a feeling Unicron would win
I was shocked that you had Unicron win, i was for sure thinking you were gonna pick Link and i’d have to debunk your claims.
Might have to debunk a few those as Unicron would WIPE the floor with Link, certainly isn’t a “narrow win”