Jon Moxley made his NJPW debut on the evening of the Best of Super Juniors final on June 5, 2019, facing another former WWE, Juice Robinson; Moxley managed to defeat him and wins the IWGP United States Championship for the first time in his career.
Four days later he beat Shota Umino in Dominion 6.9 announcing his will to enter the G1 Climax tournament. On June 13 he won the first match of the G1 Climax 29 against Taichi. Following his departure from WWE in 2019, Good reverted back to his Jon Moxley moniker and made an unannounced appearance at AEW's premiere event, AEW Double or Nothing.
He also started working in NJPW shortly after his WWE exit and won the IWGP United States Championship in his debut, becoming the first and only wrestler to have held the WWE and IWGP United States championships. During a long interview with TV Insider, he described the transition from WWE’s schedule to AEW: “The schedule for me hasn’t really let up at all.
Other than that initial month after I put my foot on the gas pedal. I did shows in Japan and AEW starting going into the summer. I also had to deal with injuries too on top of that….I just went from Jacksonville to Tokyo to Memphis to home for like 30 seconds and to Cleveland and Japan and back to Alabama.
I’m all over the place, but I feel more in control of that. It’s less someone put a trip to Japan or Australia or England because I have to. I’m excited. Even today on my day off doing media, it doesn’t feel like something I have to do because I’m passionate about this product. I want to get people in the building and help out."