Hello @Lisamull,
As of the moment, there isn't an integrated way to assign a different account to track your credit card fees of payments from your customers. The single account used for your merchant services is a way to keep a better view of all the transactions coming into your account.
Learn more about your account with this article: Update business and account information.
Additionally, I've also included this helpful article in case you need ideas on when will you receive the funds from your customers: Learn how to check when QuickBooks deposits customer payments into your bank account.
If you have any other questions, please let me know in the comments. Stay safe!
