But the Australian rugby cult hero known as the Honey Badger believes his chances of a Super Rugby comeback are slim, and says he will honour his two-year deal with the Coca Cola Red Sparks regardless of his World Cup fate.

Cummings will play for the Barbarians against the Wallabies at Twickenham on Sunday morning Australian time after his shock decision to quit Australian rugby this year to start a lucrative deal in Japan.

The winger said he would only consider a return to Super Rugby with the Western Force to repay the club for allowing him to make the move to Asia, and has held initial talks about a move back to Perth.

"Things pan out for a certain reason ... I've had a great time in Japan with some new experiences. If there is a small chance to go back to Super Rugby next year and be eligible for the World Cup, I'd take it," Cummins said in London.

"At the moment, the contract is in Japan for two years, but depending if the Japanese clubs can bend a little bit. It's probably not likely ... things have been spoken about but it's not that simple.

"They're pretty down-the-line over there and that's fine, the contract is what it is and I'm happy to go through with it, I wouldn't have signed it."

There are continual calls for the ARU to relax its eligibility rules to allow overseas-based players to represent the Wallabies.

The ARU will introduce a sabbatical clause to contracts of three years or more from 2016 to give players a chance to earn more money in France or Japan without sacrificing a chance to play for Australia.

"Australia has since changed the rules on sabbaticals and maybe [my move] contributed to that, I don't know," Cummins said.

"It was going to change at some point and I thought maybe I could help the change speed up a bit. I'm content with my decision and happy to go through with it."

There are fears of a player exodus after the World Cup with cashed-up European and Japanese clubs ready to swoop on Australia's talent, including Will Genia, James Horwill and Adam Ashley-Cooper.

Cummins said his future was "an open book" but was unsure if Australia would suffer from a mass departure.

"A couple will bail, probably more than last [World Cup] but I don't think it will be too different," Cummins said.

"Not often do you get to do a World Cup, that's why I'll get back to Japan and ask again [if I can go back to Australia]."

Cummins described his move to Japan as "adding a string to my bow", embracing the culture despite some of his "Badgerisms" getting lost in the language translation.

Cummins was referred to as a the "Honey Budger" by a local magazine and his "up the guts and swing it wide" playing philosophy draws blank looks.

But that hasn't stopped Cummins from soaking up a new experience, recently returning from a trip to Mongolia where he "lived with nomads" and went hunting in the mountains with partner Martina.

"[Martina] knows if you want to roll with the Badge, you've got to be quick on your feet," Cummins said.

"They stare at you pretty funny [in Japan], I don't think they've seen hair like this. They give you the bloody eyeballs.

"They're some of the nicest people I've ever come in contact with ... Last week we flew to Mongolia for a bit of hunting and exploring Altai Mountains. That was an experience.

"Just living with a nomad family and watching how they survive ... hunt foxes and rabbits. [Not Honey Badgers], you wouldn't catch one of them."

Cummins played 15 Tests for Australia and 74 Super Rugby games for the Force before being released on compassionate grounds.

The Wallabies have been through a tumultuous time with Ewen McKenzie quitting as coach last week and the ongoing Kurtley Beale-Di Patston drama.

"There's a bit of carry-on at the moment ... the intent is there. It will take a flushout before they can start to get some traction, but I'm sure with [Michael] Cheika in there and they'll come out hard against the Barbarians ... we'll be waiting for them," Cummins said.

"Even though the competition will be fierce, the beer after will be sweeter."