I am used to YummyFTP on Mac, later found WinSCP (A free windows sftp client) is extremly slow when you change the owner, or remove a folder. The reason is that WinSCP adopts an exhaustive approach, which means it makes a list for those files you are about to manipulate, then modify it one by one.
Luckly we could use Self-defined Command of WinSCP to run linux commands without opening a new terminal window.
Go to your WinSCP > Options > Command
Add a new command
Chown chown -R "!?Input User(Group)?www!" !& ./*
Empty the folder rm -fr ./*
Unzip unzip !