Hi there,
Probably not anytime soon? It's not that it can't be done, it's just that DMM is geo-blocked for a lot of people (Including myself) so anytime you try to visit the site it re-directs you to R18. The libraries R18 and DMM carry are so similar, most don't don't really bother with it. Especially since registration, payment, and everything else is in Japanese.
I suppose I could pay for a Japanese VPN and attempt to register and reverse engineer the DMM side, but it would take effort away that could be directed at other features (such as machine subtitle translation) which is in higher demand. It's really about directing my time at the features that benifit the most people. (^_^); But if you really feel strongly about it, feel free to make a request on my Patreon. If enough people feel this is important and want me to direct my time into it, then I can totally try and take a look!
Cheers!