I found them both on this page, which is Sonic Team's Official Japanese site. I thought the first was the old box art, and the new one below (which is rumoured to contain the game and modem in a box) had replaced it. Now I'm thinking there will be two different front covers (and Sega will sell Nintendo's modem in their game). So, can anyone translate the Japanese and sort this out?
Box 1
Box 2
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