I'm still on the lookout for ZEX-026. I really think that could be a good one based on the trailer.
From my searching, I don't know if it was ever uploaded anywhere online, and it's out of print. But on Javlibrary some screencaps were uploaded by Chinese users:
https://www.javlibrary.com/cn/?v=javlipltsm
I tried contacting one of them but they want to be paid in Chinese Yuan. Even if I wanted to I couldn't send that money from the country I'm in. And it's probably a scam anyways. But at least we know (based on the screencaps) there are some digital copies out there, so maybe it will turn up eventually. Fingers crossed!