The Storm of Clan Sakai is Jin's starting Sword Kit, the Sakai clan's own regalia. You have it from the first minute, and you can switch back to it any time after trying other kits.
Nothing to do. It is already equipped when the game begins, and it stays in your list after you collect other kits.
The kit carries the colours of Clan Sakai, the family that serves as the jito's right hand on Tsushima. It came down to Jin from Kazumasa.
Image: Sucker Punch Productions / PlayStationAzure Dragon
Azure Dragon is a Sword Kit that reskins Jin's katana and tanto. You collect it from the Pillar of Honor on the east side of the Endless Forest in Kamiagata, and it is purely cosmetic.
Bishamon's Fortune
Bishamon's Fortune is a Sword Kit that reskins Jin's katana and tanto. You collect it from the Pillar of Honor just north of Little Monk's Pond in Toyotama, and it is purely cosmetic.
Breath of Hachiman
Breath of Hachiman is a Sword Kit that reskins Jin's katana and tanto. You collect it from the Pillar of Honor between Old Kanazawa Marsh and Iijima Farmstead in Toyotama, and it is purely cosmetic.
Dueling Festival
Dueling Festival is a Sword Kit that reskins Jin's katana and tanto. You collect it from the Pillar of Honor east of Fort Ito, out in the Old Togo Rice Fields in Toyotama, and it is purely cosmetic.