Batman being inserted everywhere is a one-way-street. You don't see other heroes appearing regularly on his books, there's no "bridge of worlds" just one character that is overexposed.
During the new 52, there were the right circumstances to connect more their worlds as writers had to work with them as a couple but they didn't really do much. Right now, unfortunately there are no reasons anymore to try to connect their franchises. writers even struggle to work with their world individually. 😅Look at what their TV verses do. They break every rule in the book and bring in characters from other series and sometimes even ignore what should be in terms of the comic history for their new vision. Even the movie verses decided Diana was besties with anyone but Superman. It's double standards. Soule was doing it pretty well and got stopped in his tracks. There is an agenda against SMWW for whatever reason. Yes it might be due to movie synergy but now movie synergy has flopped, we will see if this will carry on.
Frank Miller is one who flouts rules and in his DK verse he melds many verses. People might say well that is non canon. Well there are the team up books and the other series that do it that use the wider DCU as its sandbox. From Teen Titans to Bombshells to Earth 2 to Injustice to Batman Beyond etc . When I think of some of the stuff I have read....smh. DC have humans with no warrior training pretending they can impress New Gods and fighting them as if they are seasoned warriors yet they refuse to let what is logical happen, use the elements of SM and WW worlds to create new fresh stories that don't require jumping the shark. And we have been asking for smww in a non canon series to happen. Like new 52 SMWW who, if there was any respect for creative process, should still be alive and on their earth. And writers could have a chance to visit with them for the fans that appreciate them because there are those fans out there.