Thread:UltimateDespairDaniel/@comment-44811886-20200117211614/@comment-29403514-20200117212927

The category literally says why.

"This category is for characters who originated from the Super Smash Bros series.

NOTE: This does NOT include characters who appeared in the series."

Byleth is not from the Super Smash Bros. series of games, he is from Fire Emblem.