Remote SFTP sites in both the right and left windows?

I am considering switching to WINSCP. Overall, seems like it will work, but often, I am comparing files between two SFTP sites rather than a local machine and an SFTP site. Is there a way to display remote SFTP sites in both windows? I can't seem to find that.

No, WinSCP cannot do that.
See also: https://winscp.net/eng/docs/faq_fxp