Is this idol merch or a brand on Musinsa.jpg

Source: Women's Generation (Ammana)

iKON group merchandise

That line logo is the official logo for iKON,

where the English spelling "ikon" is expressed

using the Geon-Gon-Gam-Ri trigrams of the Taegeukgi (Korean flag).

They released a lot of clothing merch

using this logo, and even looking at it now,

it's literally giving Musinsa vibes.

Not a promotion.

You can't buy this merch anymore.

Why?

Because iKON is no longer under YG.

After their contract with YG ended,

all the members moved to a different agency

as a whole team.

For reference, this merch came out

around 2016–2019.

Source: https://cafe.daum.net/subdued20club/ReHf/5659343