Use FTP or LFTP over a SOCKS proxy or SSH tunnel
Install tsocks:
sudo dnf install tsocks # OR ...
sudo apt install tsocks
Start a SOCKS tunnel over SSH:
ssh -D 6000 my.tunnel.host
Create a ~/.tsocks.conf file:
cat > ~/.tsocks.conf <<EOF
server = 127.0.0.1
server_port = 6000
EOF
Run your FTP client using tsocks and the newly created config file:
TSOCKS_CONF_FILE=$HOME/.tsocks.conf tsocks lftp my.ftp.host