Create a payment policy from the project, or from your Policies and Taxes Tab
When you are creating or editing the policy, you can select to pass either "Credit Card" or "ACH" fees, or both.
Then, when your client is paying through Stripe, they will be charged the processing fees on whichever payment method(s) you select, and you will not be charged for the processing fees.
Be sure you’re in the know when it comes to all merchant services fees by reviewing this (Article).