in most of their battles, dd is always saying/thinking - i cannot get into a hth contest with this guy - he's way faster and way stronger than me. bats is better than dd, but not THAT much better. spidey also did a good job of beating up on ironfist. though the battle wasn't over spidey clearly had the upper hand and likely COULD have ended it were ironfist not a one-time friend. in that battle it is remarked by spidey that though fist has trained a lifetime and has made his body a living weapon, the only weapons he has ever needed 'were the proportionate strength and speed of a spider' - he evades all of fist's punches in darkness relying only on his spider sense (which IS at times overrated but was enormously efective in THIS battle) to dodge the blows before he sneaks in and he clobbers fist. he also managed to web shang chi to a wall in a battle (shang somehow summoned the strength to escape by . . . breaking DOWN the brick wall . . . ???)
bats may have bombs, but one pic of spidey getting smacked by a bomb does not reveal the literally dozens of times green goblin used them and missed him, or spidey webbed them and caught them. knock out gas MIGHT work in the right situation, were they confined, but even then spidey's mask acts as a partial filter and his enhanced endurance could compensate while used his webs or perhaps tried to get in close enough to end things where he had an advantage over guys like fist and dd. i like bats a lot, but straight up, though he'd hit spidey a few times and it wouldn't be easy, in the end spidey is just too much physically, despite bats's training.
as far as spidey doesn't know bats - if the two met for the first time, it's likely BATS would be the overconfident one. he's much taller and physically more imposing than spidey. he comes across as bleak and menacing while spidey would probably be cracking wise.
if bats DID know it was spidey he was going to be fighting though, he would certainly come prepared to take spidey down by scrambling his spidey sense and having long range weapons that could take spidey out.