This is actually a decent fight IMO. Spidey has a speed and agility advantage, but he will have to get up close to try and do some damage, and Heimdall has a large pointy sword and knows how to use it. He could potentially try webbing him up, but I am not sure it would work considering how Heimdall hulk'd out of the Casket of Ancient Winter's ice. Hell, Heimdall has an Asgardian blade, so he could probably just slice through the webbing.
__________________ Never take life seriously. Nobody gets out alive anyway.
Spider-man has enhanced reaction time and the spider sense so in a fight he has an advantage as far as senses go imo.
__________________ Chicken Boo, what's the matter with you? You don't act like the other chickens do. You wear a disguise to look like human guys, but you're not a man you're a Chicken Boo.
Garfield Spidey's "spider sense" failed him a few times. Heimdall broke free after Loki froze him so being webbed up if Garfield Spidey gets the chance won't matter because once that happens then Parker is dead