The series, which also features Hayden Christensen reprising his role as corrupted Jedi apprentice Anakin Skywalker, begins 10 years after the events of the 2005 film Star Wars: Revenge Of The Sith.
Appearing on the first of four British GQ covers dedicated to GQ Heroes, McGregor said: “There’s a lot of homoerotic Obi-Wan/Hayden (Christensen) fan art that gets sent to me now and again … it’s always a bit of an eye-opener.
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“You open the envelope, you think you’re going to have to sign something, and you’re like, ‘F*****g hell!”
McGregor also spoke about collaborating with director Danny Boyle, with the pair first working together on 1994′s Shallow Grave before they reunited for 1996′s Trainspotting and then A Life Less Ordinary in 1997.
In 2017 Boyle spoke of his “great shame” over a 10-year fall-out with McGregor, caused by him not casting McGregor in his film The Beach, which saw the leading role go to Leonardo DiCaprio.
But the pair buried the hatchet and appearing on the Graham Norton Show, Oscar-winning director Boyle said: “I handled it very badly and I’ve apologised to Ewan. I feel a great shame about it that is difficult to explain.
“He handled it with enormous grace and courage. Someone asked him to present an award to me for Slumdog Millionaire and he did it and made this amazing speech and I was in tears backstage. I’m very grateful to him.”
Speaking about his relationship with Boyle in the 90s, McGregor told British GQ: “I felt Danny Boyle was changing British cinema, and I was part of it.”
McGregor and Boyle also teamed up for 2017 film T2 Trainspotting, the follow-up to the ground-breaking 1996 hit which also starred Jonny Lee Miller, Ewen Bremner and Robert Carlyle.
The actor, 51, shared his love of the band Oasis and said of his relationship with fame: “I don’t feel like that guy anymore.
“I don’t have the same relationship with my fame. That’s to do with age and experience, also just a realisation of what works and what doesn’t.
“At that time, there was a hedonistic side to my life which ended up not suiting the rest of my life.”
Writing in his editor’s letter, Adam Baidawi, British GQ’s head of editorial content and deputy global editorial director for GQ, said: “Sometimes heroism is loud. Sometimes it is whisper quiet. But I don’t believe there is heroism without flaws.
“Heroism is acting in spite of our shortcomings or protective instincts. A hero is simply an ordinary person who rose above themselves.
“We’ve programmed our 2022 Heroes event — and the pages of this issue — to be a killer cross-section of this fresh idea of a hero.”
The July/August issue of British GQ is available via digital download and on newsstands from June 28.