Are you looking for "Display completed transfer in queue for > Forever"?
https://winscp.net/eng/docs/ui_pref_background

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And maybe for this request:
Issue 1041 – Optionally show elapsed time on the transfer queue list and keep it displayed after transfer finishes
(you can vote for it)

Add Log Windows Include History For Transfer Files event after finish transfer ( Like size + files name + transfer time duration + transfer distenation or path location ) also put timestamp for each line in log