Spiderman 2099 is like Spiderman except his abilities surpass Spiderman’s regular ones. Venom also has better skills than regular Spiderman. They are both almost equaly matched but Venom has possesed Thor in the past. Venom wins.
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Just because venom has absorbed a host doesn’t mean that the symbiote controls their powers as well Spiderman wins since he is just peter parker who got on a rocket to the future when he saw venom and carnage hitching a ride.
Spiderman 2099 is still a fighter but Venom has the powers of Thor and Hulk to win.