So, we know that sentient beings swallowed by rimuru do both stay alive and keep their abilities, as we saw with ifrit and veldora, assuming this applies to skills too, if rimuru swallowed a full power veldanava, would veldanava be able to use beginning eden inside of his stomach and just create an entire world in there? I guess ultimately it boils down to whether or not rimurus stomach actually has a capacity and whether or not rimurus stomach is even recognised as a space that's free game for beginning eden to work on.
Also, just for clarification, I haven't actually read the lns so if I've overlooked sumn regarding the functioning of rimurus stomach or beginning eden that's why