Kagehina:

Hinata tries to be the big spoon but fails so he becomes the little spoon

Bokuaka:

They switch

Iwaoi:

Lol Iwa doesn't like spooning so they only hold hands

Kuroken:

Just like Iwa, Kemma doesn't like spooning so Kuroo just (tries to) hugs him

Daisuga:

Suga is totally the little spoon so Daichi is big spoon.

Tsukiyama:

They rarely spoon but when they do Tsuki is the big spoon