who is the mother of luffy

She could be a former pirate captain herself. Maybe she was one of the most feared pirates in her time, and her skills and reputation were passed down to Luffy in some way, even if he didn't know it was from his mother.

No, it wasn't. Oda had made it clear that Luffy's mother was not part of One Piece and that the character would not appear. Furthermore, if Sir Eam was Luffy's mother, it would be very illogical. This was because Luffy was one of the people Sir Eam had 'killed' back then. It was impossible for a scene where a mother killed her son to happen.

In One Piece, Luffy's mother was not explicitly mentioned. Oda had once said that mothers were the natural enemy of adventure. Luffy began his adventure after leaving his mother's embrace, so Luffy's mother was not part of the story he told and would not appear. However, there were many speculations among the fans. For example, some people guessed that it was Seven Martial Haisha Krokdal. The reason was that Old Sha looked like a girl in a photo when she was young. Ivankov could change people's gender and said that Old Sha had something on him. They speculated that Old Sha used to be a princess of a fallen country. After being saved by the dragon, she fell in love and gave birth to Luffy. Later, Ivankov turned her into a man. There were also people who guessed that it was Sir Eam, because Sir Eam was holding Luffy's bounty and had the same huge straw hat as Luffy in front of him. However, after Luffy's voice actor, Makoto Tanaka, asked Oda for confirmation, this speculation was denied. There were also people who guessed that it was Luffy's hometown, the owner of the Windmill Village bar, Makino. However, Oda's drawing of Makino holding a child overturned this speculation. There were also people who thought that it was the red-haired sisters, but there was no conclusive evidence.

There could be an original character created just for the fanfiction. A woman with a kind heart but a tough exterior, who was a great fighter. She could have met Luffy's father during a battle and they fell in love, and she became Luffy's mother.

Sir Eam wasn't Luffy's mother. Oda once said that his mother was not part of One Piece's story and would not appear. Luffy's mother did not belong to this story. From the logic of the story, if Sir Eam was Luffy's mother, it didn't make sense for him to kill Luffy. Moreover, judging from Eam's gaze in the animation, the possibility of Eam being a man was extremely high. So, Sir Eam wasn't Luffy's mother.