SEGA has plans to release new games from Sonic the Hedgehog next year. In 2021, the 30th anniversary of Sonic will be celebrated.
In a document for licensees is an ad from SEGA identifying a number of milestones for Sonic-related products. At the bottom is a heading identifying Sonic’s 30th anniversary in 2021. On pages 90 and 91, 2021 will be a year of celebration with new games, digital content, events, major announcements and a licensing program tailored to it.
It has not yet been announced which new games are involved. Currently Nintendo is celebrating Mario’s 35th birthday with big plans, including the announcement of Super Mario 3D All-Stars for Switch.