No. The Sonoff boxes are just smart relays and rely on a constant power supply. As soon as you pull the cord, the Sonoff is dead.
What you possibly want is a Fibaro switch. But you need to check your wiring on the pull cord first. We have a switch in the kitchen for example that is about as dumb as you can get so it just has the live going through it and the switch breaks or makes the circuit. With the Fibaro, if I understand them correctly, the switch sort of becomes a low voltage switch to control the relay. They're not cheap but I've heard very good thing about them.
If you can access the live feed, switched live and neutral above the light fitting then what about a Sonoff relay which supports NO & NC contacts. This way you can wire the pull switch in to create a 2 way circuit.
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