Seeing Necky the Fox in that scan of Famitsu has left me intrigued. Who is he? What is his purpose? It seems that he is a character from Susumu Matsushita, a Japanese cartoon company, and features regularly in Famitsu magazine alongside other video game characters. And that can only mean one thing.
Yes, there are some Sega-related ones! Unfortunately there are only two that I could find, but at least they have Dreamcasts in them!
This first one has Necky piloting a Dreamcast controller towards the Dreamcast mothership (?). It reminds me of those '80s Oliver Frey covers whereby ZX Spectrums would be flying in space.
Next is a picture of Father Christmas, with lots of Necky elves helping make Dreamcasts for all the little boys and girls. Clearly not enough people ordered one for Christmas then, as we all know where the Dreamcast eventually went.
As Famitsu is weekly, and there are no cover archives anywhere, there are probably countless more Sega-related ones. These were the only ones I could find off the Susumu Matsushita website, so if I find any more, I'll post them!