The Shrimp Kicks version is the one used in Squid Beatz.
Trivia
DJ Lee Fish is one of the four artists to have a symbol resembling a Parental Advisory Label on their album art, the others being Turquoise October, the Squid Sisters, and DJ Real Sole.
DJ Lee Fish's English name is a pun on "jellyfish", while their Japanese name, "Lee F.", can be read as "reef".
The four versions of Lookin' Fresh played in Booyah Base reflect each store and its shop keeper:
Annie's has louder treble, i.e. vocals, and minimal percussion, giving it a weaker sound in that respect. This is a reflection of her shy, detached personality, as well as the fact that she sells gear for the top part of the buyer's body, hence the emphasis on the treble.
Jelonzo's music is faded out except for the melody, the "center", because his gear goes on the middle part of the body. It also has many bubbly sound effects in the background, showing his bubbly and ecstatic personality as well as referencing his gelatinous species.
Crusty Sean's has the bass turned all the way up and emphasizes percussion because his gear corresponds to the lower part of the body. Furthermore, the heavy beat gives it a bouncy sound, reflecting his outgoing personality.
Sheldon's music is more distant, showing his separation from the others as a weapons dealer. It also has static and other sounds reminiscent of a military radio, as a reference to his obsession with the military.
While DJ Lee Fish's songs don't have any significant presence in Splatoon 2, a muffled portion of the Shrimp Kicks version of Lookin' Fresh can be heard from the Crust Bucket in Inkopolis Square, referencing how both Shrimp Kicks and the Crust Bucket are run by Crusty Sean. Additionally, the shop song in Splatoon 2, DJ Real Sole's New You, has musical interpolations of Lookin' Fresh.
