Hello,
Welcome to our Pre-Sales Question channel 🙂
We don’t have any current integration with Sagepay nor am I seeing any plans of doing so, but there are a number of customers using Sagepay without conflict as far as I know. We offer a 30-day money back refund, so if you wanted to try it out to see how it works together, that’s always an option. Another idea would be to visit our UserVoice Feature Ideas page and submit the integration as a request.
I hope this answers your question and please let me know if you have any additional questions or comments. Have a great week. Cheers!