If Monkey D. Luffy had acquired Sung Jin-Woo's powers as a Devil Fruit and retained his own, let's imagine how this could impact the One Piece world.

Devil Fruit Power Acquisition: Luffy consumes the Sung Sung no Mi (Sung Sung Fruit), a mythical Zoan-type Devil Fruit. This fruit grants him the abilities of Sung Jin-Woo, the protagonist of Solo Leveling. Additionally, Luffy still possesses the Gomu Gomu no Mi, which gives him his rubbery powers.

Training and Adaptation: Luffy's training regimen becomes more structured, thanks to Sung Jin-Woo's disciplined nature. He learns to harness the powers of the Sung Sung no Mi through rigorous solo missions and mastering various abilities like Shadow Exchange, Summoning, and Monarch's Dominion. His time management and tactical skills improve significantly.

Likes and Dislikes: Luffy's love for adventure and meat remains, but he also develops a fondness for Sung Jin-Woo's passion for solo hunting, strengthening, and overcoming insurmountable odds. His dislikes would still include oppressive tyrants and anyone who threatens his friends.

Changes in the World: Luffy's newfound powers would make him an even more formidable force in the Grand Line. The ability to summon creatures and manipulate shadows would give him an edge in battles. His gradual mastery of Sung Jin-Woo's powers could lead to alliances with other powerful individuals, perhaps even some of the Yonko or the Marines.

Descriptions of Powers and Moves:

Rubber-based Powers (Gomu Gomu no Mi):

Luffy retains his elasticity, granting him immunity to blunt attacks.

His Gomu Gomu no Pistol and Gomu Gomu no Gatling Gun techniques become even stronger due to his enhanced physical capabilities.

Sung Jin-Woo's Powers (Sung Sung no Mi):

Shadow Exchange: Luffy can switch places with his shadow, allowing for instant teleportation and tactical positioning.

Summoning: Luffy can summon powerful creatures to aid him, similar to Sung Jin-Woo's summoning magic beasts.

Monarch's Dominion: Luffy's mere presence exudes an aura of power that can intimidate foes and weaken their resolve.

Berserker's Roar: He can emit a powerful roar that disrupts the focus and coordination of enemies.

Shadow Monarch's Heart: Red-Gate: Luffy can create a giant gate, connecting to a shadowy realm where he can draw on immense power and unleash devastating attacks.

Solo Monarch's Authority: Luffy gains control over his territory and can manipulate the battlefield, strengthening himself and weakening his enemies.

Arcs and Events:

In the Alabasta Arc, Luffy uses Shadow Exchange to swiftly counter Crocodile's sand-based attacks.

During the Enies Lobby Arc, Luffy summons a shadow beast to help in the fight against CP9.

In the Marineford War, Luffy's Monarch's Dominion strikes fear into the hearts of even the Admirals and Warlords.

The Dressrosa Arc sees Luffy using Solo Monarch's Authority to create a shadow realm, giving him the upper hand against Doflamingo.

Conclusion: Luffy's acquisition of Sung Jin-Woo's powers as a Devil Fruit, in addition to his existing Gomu Gomu no Mi abilities, would turn him into an even more formidable and strategic pirate. His journey in the world of One Piece would be marked by incredible solo battles, the formation of new alliances, and a reputation as the ultimate "Shadow Pirate." This unique combination of Devil Fruit powers would make Luffy a major player in the ongoing struggle for power in the Grand Line.