Lad Bible has done an interview with Sonic Team's Iizuka and it has just been published. We will highlight segments here but please go read the full interview.

When talking upcoming Sonic games:

Team Sonic Racing comes out for the expected platforms on 21 May, and might not be the only Sonic game we see in 2019. Perhaps it’s a quirk of translation – Iizuka-san speaks Japanese, I don’t, so we converse through a very helpful middleman – but he makes a reference to there being Sonic titles, plural, in development right now.

On the upcoming movie:

 “It’s not a SEGA movie – we’re not making it, or anything – and I’m only an advisor, really. But I do get shown things, and the [movie team] ask for my opinion. I’m also listening to what the fans are saying, and I’ll feed that back to the director – he, and the producers, are very interested in receiving that feedback. At the end of the day, it’s up to the team at Paramount to make something successful, but we’re all looking forward to seeing the finished movie.”