I’ve not used it myself, but there is the Azure Face API in the Marketplace.
https://marketplace.mendix.com/link/component/109052
You’ll need an Azure account to be able to use it, and there could be an additional cost involved with this.
Looking at the documentation it looks like face verification is offered by the API.
https://azure.microsoft.com/en-us/services/cognitive-services/face/#demo
You could probably use the Take Photo action from the Web Actions module in the Marketplace to take a photo to pass into this API.
https://docs.mendix.com/appstore/modules/web-actions/
Good luck with the application.