Yes, for PRO subscribers.
When you export projects or individual loops from Overtune you get a license that details permitted and forbidden use cases. You may use the loops you export commercially. Overtune will never ask you for royalty payments or enroll you in royalty-sharing schemes of any kind.
Note that some distributors might still require you to disclose the use of any licensed third-party material in your creative work, even if they are royalty-free.
Artists on the free plan are not allowed to use Overtune loops in commercial purposes.