You may be wondering why all of your leads syncing through Formstack Sync are getting assigned to one owner in my CRM. The reason for this is because by default Formstack Sync will assign the owner to be the user setup to authenticate the system in question.
For example, if you are authenticating your CRM and you are required to provide a users credentials or a specific users authentication token, by default any new records that get created by the Formstack Sync in this CRM will have the owner set to this specific user.
If you want to change up who the owner is by default, simply change the user credentials to the appropriate owner (just make sure they are the right type of user based on the requirements for the connector in question).
Other ways to control/change the lead owner is to use the lead assignment rules in your CRM, or use a workflow in your CRM to sync lead owner value to a custom field. This option is not managed directly in Formstack Sync, however, Formstack Sync can be used to pass over fields from another system that can help trigger these rules or workflows that then set the owners.