Hi.
Install testing version on the plugin where incorrect frontend tax display was fixed https://s-plugins.com/testing-version/
Or wait before new version with the fix is released (should be very shortly).
Regarding your original question, won’t the tax itself work for you? You can rename tax to something like “handling” using free Custom Messages addon https://s-plugins.com/stripe-payments-custom-messages-addon/
If this not an option, there is no other proper way of doing it right now. I have created a ticket in our system to implement something that could be used for this purpose, but at the moment cannot give you any ETA on this.