You can’t modify how bounce rate is calculated but filtering out data can do the right trick for you and show you the required data. Below are some of the ways which can help you see data for new visitors only
You can exclude returning visitors by following
– set up filters within the report
– create custom reports
– setup advanced segment
– create a separate view to show new visitors only
see the original question: https://www.en.advertisercommunity.com/t5/Filters/Exclude-returnig-visitiors-from-bounce-rate/m-p/594654#M1978