The offences are alleged to have taken place between 2022 and 2024.
Police said the charges follow an investigation which commenced in 2024, adding that a woman is being supported by specially-trained officers.
Paul Gallagher is a year older than Noel, and seven years older than Liam.
The three brothers grew up together in Burnage, Manchester, but Paul has never been involved with the band.
Oasis are currently on a hugely successful reunion tour, having played shows in Cardiff, Manchester and London, with further dates to come in Edinburgh and Dublin before the tour heads to North America.