The two victims, aged 64 and 36, sustained stab wounds during an altercation at a fairground on Ruscote Avenue on July 25.
Samantha Halliday was charged by police the following day and appeared at Banbury Magistrates Court on Thursday (August 30).
The 26-year-old woman, of Horton Drive, Banbury, is next due to appear at Oxford Crown Court on September 28.
Two other men – Tom East, 27, of no fixed abode, and Gary Woodwards, 25, of Middleton Road, Banbury – were also charged with two counts of wounding with intent.
Woodwards was also charged with threatening a person with an offensive weapon in a public place.
They pleaded not guilty to all charges at the crown court on August 24 and were remanded in custody ahead of a trial on January 7.