There is already a feature in the product that allows user to access the organization without having to wait for the background synchronization. For example, if you have licensed a new user or added a new user to the security group, there is no need to wait to use the product.

New user can just open their organization url directly, for example: https://myorgnam.crm.dynamics.com/

On login, system automatically creates the user in the organization if they meet all the access requirements