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Gen 8 introduces 80 new mons.
15 of them define the current OU, varying between S rank and B+ rank.
20 of them are considered wholly unviable and struggle to remain relevant even in ZU.
45 of them are not fully evolved. Of those, 2 are viable in LC and 1 is LC Uber.
In regards to in-game teams, none of this matters. The game can easily be beaten with the starter Pokemon and/or any Pokemon caught on Route 01.