This project outlines the design of an adapter which allows the Sharp MZ-700 to be used with a single expansion card.
Normally an MZ-700 would require the MZ-1U06 expansion unit to add expansion cards but these units are as rare as the proverbial rocking-horse excrement!!!
The adapter can be made with a vertical or horizontal MZ-700 expansion card as can be seen here: https://twitter.com/engineerswork1/status/1640438637006553088
Either submit the latest release zip package in releases/ directory to a PCB fabrication plant or contact me as I may have spare.
My website, https://eaw.app will have full build instructions in due course.