The World of CD-i found two sources that actually say that Sonic Eraser was planned for CD-i in Japan/Brazil for the ill-fated Meganet service. Meganet was an online service that Sega started in 1991 to allow Genesis users to download games on their Genesis/Mega Drive. The game itself is like a Columns version with a sonic sprite in it. But why do they mention a CD-i version?
The Meganet service was launched in 1991 in Japan. Philips also built an online service to be used with their CD-i system in 1995-1996. It is always interesting to see how these techniques are developed by different companies at the same time. Did they help each other? Was there any link between the TeleGenesis (announced for the USA but never released) and Web-i from Philips? Is there any link with the Meganet service that was relaunched in Brazil in 1995?
The internet doesn't give away this secret now, so we have two sources that simply claim a CD-i version was in the planning. It seems highly unlikely but stranger things have happened in the past!
[Sources: Sonic Scene and Nostallgia Brasil]