There should not be limit of total transferred files.
But there might be a limit of how many files in a single folder WinSCP can handle.
What is your largest folder?
Can you post a log file?

Hi there,

I'm trying to migrate about 140 million files in many subfolders and getting out of memory errors. Before I go down the rabbit hole of trying to find the right settings, is this even possible? are there any limitations to move this number of files?