It's impossible to definitively say whether Luffy in Gear 5 could defeat Shanks. Both characters are incredibly powerful and have demonstrated immense strength and abilities.
Analyzing Luffy's Gear 5
- Awakened Devil Fruit Power: Luffy's Gear 5 utilizes his awakened Zoan abilities, granting him immense strength, durability, and the ability to manipulate his surroundings.
- Enhanced Elasticity: Gear 5 enhances his elasticity, allowing him to stretch and contort his body in unimaginable ways.
- Caricature-like Abilities: Luffy's Gear 5 manifests as a cartoonish, exaggerated form, allowing him to manipulate reality to some extent.
Assessing Shanks' Capabilities
- Haki Mastery: Shanks is renowned for his exceptional Haki mastery, particularly in Conqueror's Haki.
- Swordsmanship: Shanks is a skilled swordsman, wielding a powerful blade that can cut through anything.
- Unknown Abilities: Shanks possesses several unknown abilities, possibly related to his Devil Fruit or Haki.
Conclusion
While Luffy's Gear 5 is incredibly powerful, Shanks' experience, Haki mastery, and unknown abilities make it difficult to definitively declare a winner. The outcome of a potential battle between these two characters remains uncertain and highly speculative.