They have been producing all officially-licensed retail jerseys with a Nike or Fanatics branding for the NFL since 2020. Fanatics owned sites include Fanatics, Fansedge, NFLShop, Lids, Sports memorabilia, JC Penny, and others. They are inevitable. Legitimate is used synonymously with licensed with respect to determining authenticity of a jersey.

​https://www.reddit.com/r/nfl/comments/1d7mhnm/an_nfl_fans_guide_to_jerseys_in_2024/