Nintendo have just announced on their Japanese website that like Sonic Advance 1 and Sonic Advance 2 before it, Sonic Advance 3 will also be released on the Wii U VC in Japan on May 25th. Also like the first two games, Sonic Advance 3 will cost ¥702.
Unfortunately there’s still no word on a western release of any of the three games. This is likely due to the fact that THQ and Infogrames published the games in the west, and neither exist anymore. THQ did all the NA releases, while Infogrames did 1 and 2 in EU while THQ took over for the 3rd in EU.
Via Nintendo’s Japanese page for the game.