The 23-year-old has signed on a one-month loan deal from National League Aldershot Town and will be eligible to feature for Farnborough in The Emirates FA Cup.
Francis found the net 29 times in a freescoring Hayes & Yeading United side last season and was named as Player of the Year for 2021/22.
Impressive figures throughout the last campaign earnt Amartey a two-year deal with Mark Molesley’s Aldershot Town back in June.
Formely of Birmingham City, the lively striker has also turned out for Hendon, Slough Town and Braintree Town during his time in Non-League.
Manager Spencer Day said: “Absolutely thrilled! Franny Amartey, who we obviously know very well, has come on an initial month’s loan. We’re very grateful to Mark. That’s a fantastic bit of business.
“We’ve been working hard to try and bring in strikers. We’ve been trying to bring in Franny for some time. Delighted to get him. The pace we have in our team now is quite scary. We’re very excited and build everything towards Saturday.”
Midfielder Kenny Davis also moves in the opposite direction and will spend a month on loan at Aldershot Town in a bid to regain match fitness after injury.
The experienced midfielder will be available for The Shots for a busy period ahead with trips to Chelmsford City, Yeovil Town, Dorking Wanderers, Torquay United and home clashes with York City, Dagenham & Redbridge and Maidenhead United.