Concurrently, Takahashi was making a name for herself as a singles competitor, winning the AJW Championship on March 1, 2000, and the junior division competition at that year's Japan Grand Prix.

At an independent show held on July 14, 2006 to celebrate her tenth anniversary in professional wrestling, Takahashi announced her intention to start her own promotion.

On October 1, 2006, Takahashi defeated Africa 55 for the resurrected AWA World Women's Championship at the debut of her new promotion, Pro Wrestling Sun.

[5] On July 17, Takahashi returned to the United States, making her debut for Ring of Honor (ROH) in Las Vegas, Nevada by defeating ODB.

[8] On September 7, 2010, Takahashi announced with Fuka and Rossy Ogawa that they founded a new promotion called World Wonder Ring Stardom.

[16] At Stardom in Showcase vol.2, a non-canon event produced on September 25, 2022, Rossy Ogawa was a victim of various "grim reaper masked silhouettes" who kept attacking him.

[17] Minutes later, a video of Alpha Female was played, showing her criticizing the current situation in Stardom as she was announcing her return to the company on October 23, 2022 for the IWGP Women's Championship tournament.

[17] At the 2022 Goddesses of Stardom Tag League, Takahashi teamed up with Yuu as "7Upp" and won the whole tournament by winning the "Blue Goddess Block" with a total of eleven points scored after competing against the teams of FWC (Hazuki and Koguma), MaiHime (Maika and Himeka), The New Eras (Mirai and Ami Sourei), BMI2000 (Natsuko Tora and Ruaka), 02 line (AZM and Miyu Amasaki), Kawild Venus (Mina Shirakawa/Waka Tsukiyama and Saki), and wing★gori (Hanan and Saya Iida).

[18] On April 15, 2024, Rossy Ogawa held a press conference to announce his new promotion Dream Star Fighting Marigold, with Takahashi being one of the initial roster members.

[19] On December 13, 2024, after unsuccessfully challenging Sareee for the Marigold World Championship at Winter Wonderful Fight, Takahashi announced that she would be retiring from professional wrestling in May 2025.