Hope you are doing well and sorry to keep you waiting.
We have got this checked with our development team, and found that the option to generate the podcasts in Hindi language is not yet present. The team is already working on this feature and it would be available in the future updates.
Please allow us some time to check with the team if it is available in Hindi. We will update you with the correct information. In the meantime you may refer to the following help document for more information about the feature: Create podcasts from PDF Spaces on mobile.