The island that Bege first encountered in the new world is extremely peculiar. It almost seems like a moon, with this island having its own gravitational, or perhaps electromagnetic, pull.
Afterward, the next time we see Bege is two years later as a member of the Big Mom pirates. Now we have no idea what this island is, in all likelihood, its probably just a scrapped idea that Oda just came up with on the fly as a cool visual. However, its also very possible that this is something Oda could expand on later.
If so, then I think it is very likely that this island is a super homie created by Big Mom, possibly by using her awakening on God Valley.
Given how Bege's next appearance was as a big mom pirate, if this island belongs to anybody, its likely to the BMP. Furthermore, it would be a good candidate for God Valley, as we know that GV disappeared but we also have no idea what happened to it. It couldn't have been Imu's weapon, as Dragon's statement suggests that it wasn't used until recently. So BM is a major culprit for who could have gotten rid of it.
Lastly, I think this could be a massive homie created by BM's awakening as in Wano and WCI, many fans were left with the impression that BM's feats were underwhelming. While we got massive island busting attacks from Kaido and Luffy, we never really saw something on the same level from BM. I think BM having a massive trump card like this up her sleeve would do a lot to fix the disparity between her feats and portrayal.
As we know, BM heavily underestimated the Supernova when she came to wano. She only brought half her crew with her. Given how much she underestimated them, I wouldn't put it past her to have a massive trump card that she didn't bring to wano because she didn't think the Supernova could possibly defeat her. As for her awakening, given how BM's DF works, its very possible that her awakening is very limited. Using it takes up a lot of lifespan, so she can only use it to create one homie.
Anyways, I think Katakuri or maybe even BM herself will go and fetch the God Valley homie in order to take back Pudding from Blackbeard. Oda will then use this to hype up Teach in the upcoming arcs.
