Unlike other rumor-labeled posts, this one mainly exists for speculation means, as the bit of news that started all the hypothesis-mongering Internet theories is originated by an official press release by the American branch of Bandai Namco. On January 13th, one of the Western branch's press releases was bringing the following title:
BANDAI NAMCO Entertainment America Inc. Confirms Dragon Ball XENOVERSE 2 (Working Title) Coming to Nintendo Switch in the Americas, with Tales of and Taiko Drum Master in Development
Despite the proper body of the press statement being only about the latest home console Dragon Ball game's porting, the mere mention of the localized title of the series as part of that title has already galvanized more than one people around the Internet, with the assumptions of the future Switch Taiko game being aimed to more than one geographical area sprung by the fact of the Taiko no Tatsujin series in press releases being usually relegated to the Japanese branch's officially-released statements. As usual, the only way to find out if this scenario will turn out to be true is to wait...
The press release has been mirrored by videogame website Gamasutra as part of their partnership with the PR-related website GamesPress.