Yes, you can use a file mask with a time constraint:
https://winscp.net/eng/docs/file_mask#size_time

But I'm not sure it will give you what you want. It might only save some computation. But what usually takes most time if fetching the remote and local file lists. And the filtering won't help there.

Is there any way to only sync files created/modified on a given day? I have a NAS with 100k+ files and only 20-50 are created/modified each day and did not want to have the system compare all files with the FTP site. I was hoping the system could look at the folder and select only todays created/modified files and upload those.