Here, have my headcanon as spoilers
Confirmed by hellofrens from Worstgen
- Last chapter Bonney was stuck in the Eddy current because she just came from Egghead
- When she was there, she turned Vegapunk from an older lady into a little girl, similar to how Law caused chaos when he arrived at Punk Hazard
- The name of the island is a put itself. In Japanese, "Egghead" is translated with the Katakana インテリ ("Intelli"), being short for the English "Intelligent", a reference to Vegapunk most likely