Scoring actions the difference between Add lead and Push lead

Hello Community,

In a Scoring profile with Profile Scoring Actions.

I've been told that "Push to External CRM" updates existing leads in the CRM, it doesn't create new leads.

My question is does "Add Lead to External CRM" only add new leads to the external CRM or does this action also update existing?

or do I need to use both in my Profile Scoring Actions?

Best regards

Justin