Looks like Paramount is really pleased with how the Sonic the Hedgehog movie did, as they've officially announced a sequel. This movie follow-up will see Jeff Folwer return to direct, while Pat Casey and Josh Miller will handle the script. Neal H. Moritz, Toby Ascher and Toru Nakahara are producing, while Hajime Satomi, Haruki Satomi and Tim Miller are executive producing.
The film is still in the developmental stage, so there's no start date for filming. We also don't know which actors will be coming back to reprise their roles, but I would imagine the principle cast will likely return.