Llewellyn was paired with Scarlets’ James, 6ft 4in, for the first time against Japan.
It was Steve Tandy’s sixth different centre partnership and signalled a move away from Wales’ policy of fielding a ball-player in either Joe Hawkins or Ben Thomas in midfield.
“I really enjoyed it. It was the first that I have played with Eddie and I thought we played pretty well together,” said Llewellyn.
“The first week of training was about making sure we had the combination locked down and I felt that happened really quickly.”
Llewellyn has had 12 on his back just once for Gloucester this season and his only previous start at inside centre for Wales was against England in a World Cup warm-up game in August 2023.
It is where the former Cardiff back sees his long-term future.
He said: “The roles are definitely different. At 12 you get a lot more direct tackles and at 13 you get a few more opportunities when you are out in a bit of space.
“I enjoy playing both and I am fortunate that I can play both, but in the long-term 12 is where I will probably be.
“I think that is where I could get the best out of myself going forward. I enjoy both positions, and they both have different opportunities, but the physical aspect of the game at 12 suits me.”