Yes you could. Octopus only allow one make of inverter to do that right now and mine is not approved.
But I have 4.2kWh storage only, you would need more which is why cars are interesting.
The lowest ican buy in 15.44 p per unit and export at 27.44p max. Assuming 10% losses you would make money.
Each 2.1 kwh battery is £1k roughly so at 10p per unit that a say 20p per day savings.
