AKA Universal Video Converter
I’m not sure which arcade-specific downscaler is more scarce; the MIMO Genius II, or the UltraCade uVC by UltraCade Technologies. Very little is known about these scalers, apart from being able to downscale 480p to either 240p or mid-resolution 384p (24KHz). Judging by the screenshots in this link that compares it to the Extron Emotia (known to blend 2 adjacent fields), the uVC appears to output a blurrier, and less conformed 240p downscale.
See the links below for further information:
https://www.emphatic.se/ultracade.html
https://www.retroblast.com/reviews/Ultacade_uVC-03212006-01.html
https://service.globalvr.com/downloads/ultracade/components/040-uvcmanu-uct_uvc_user_guide_v03b.pdf