If you want some free Genshin Impact outfits, all you need to do is log in anytime starting now through update 2.5.
Genshin Impact Free Skin List - How To Get & Looks - GameWith
Genshin Impact 3.8 Patch: New outfits, free character, Bottleland map and banners
Xingqiu's outfit can be obtained for free through the new 4.4 event : r/Genshin_Impact
Genshin Impact Free Skin List - How To Get & Looks - GameWith
The Free Character Outfit Team is Here! : r/Genshin_Impact
PSA: You can claim some free Genshin Impact outfits just for logging in
Full list of Genshin character outfits: How to get, price
Giving characters a 7th constellation Part 1: Starters : r/Genshin_Impact
Full list of Genshin character outfits: How to get, price
PSA: Claim the Rais Commando outfit and Stay Human outfit for free (TechlandGG Goodies Tab) : r/dyinglight
Genshin Impact: How To Buy Jean Summer Skin