Sidney glass vs Beerus the destroyer: Beerus will wipe the floor with Sidney, Beerus is a god and Sidney is a mortal, Sidney doesn't have god ki like beerus or any god like transformation like Toppo, Goku or Vegeta. So its clear that Beerus is way stronger than Sidney, but there are some things Sidney could do to get stronger.
1: obtain god ki: Sidney could obtain god ki in a lot of different ways, he could gather the super dragon balls and summon super shenron and wish for god ki or to become a god. sidney could train with beerus in order to become an hakaishin and fight beerus toe to toe.
2: ultra ego: We haven't seen the full strength of ultra ego yet in the manga, but it is a form of the hakaishin and has god ki or requires god ki to be used, and remember sidney could get god ki by training with whis and beerus, wish for it or undergo a ritual
that gives the a god like form and ki.
3: become a saiyan: Sidney can wish to become a saiyan with the super dragon balls. He could do the super saiyan god ritual and become a saiyan god, then he can go super saiyan while have god ki, Super Saiyan god Super Saiyan.
4: he can obtain ultra instinct: Humans (mortals) can obtain ultra instinct, master roshi used it against jiren in the dragon ball super manga, and we saw goku use it, both roshi and goku are mortal and so is sidney, so he could obtain ultra instinct.
Even if sidney does have ultra instinct, he still wont be able to beat beerus, but still would give beerus a run for his money.
Yet we havent seen beerus at his full power and we havent yet seen a mortal beyond angel power.
So beerus wins and sidney loses.
1: obtain god ki: Sidney could obtain god ki in a lot of different ways, he could gather the super dragon balls and summon super shenron and wish for god ki or to become a god. sidney could train with beerus in order to become an hakaishin and fight beerus toe to toe.
2: ultra ego: We haven't seen the full strength of ultra ego yet in the manga, but it is a form of the hakaishin and has god ki or requires god ki to be used, and remember sidney could get god ki by training with whis and beerus, wish for it or undergo a ritual
that gives the a god like form and ki.
3: become a saiyan: Sidney can wish to become a saiyan with the super dragon balls. He could do the super saiyan god ritual and become a saiyan god, then he can go super saiyan while have god ki, Super Saiyan god Super Saiyan.
4: he can obtain ultra instinct: Humans (mortals) can obtain ultra instinct, master roshi used it against jiren in the dragon ball super manga, and we saw goku use it, both roshi and goku are mortal and so is sidney, so he could obtain ultra instinct.
Even if sidney does have ultra instinct, he still wont be able to beat beerus, but still would give beerus a run for his money.
Yet we havent seen beerus at his full power and we havent yet seen a mortal beyond angel power.
So beerus wins and sidney loses.