To overlook is a type of ignorance without purpose, without recollection, without knowing. It is passive Although, to overlook also suggests that the "ignorance" was performed with the eyes, since it is indeed conjoined with the verb
Overlook isn't exactly the opposite of ignore because it is limited to vision. You can overlook:
Therefore, oversight is only passive ignorance using the eyes.
But, you cannot overlook a smell, a taste, a feeling, or a sound.
English also has the words oversee and overhear, but neither indicate tru ignorance, but rather happenstance.
So the real "cousin" to ignoring something would be to miss, or to fail to notice, fail to acknowledge
They failed to notice the smell of pungent feet in the room
We failed to acknowledge that Peter was in pain
I missed the chance to hear hummingbird mating call
Each of these suggest an unintended form of ignorance,.. passive ignorance.
To ignore suggests that someone actively ignored something. It doesn't matter which sense is used.
I ignored the smell of horse manure in the background
We ignored the stickiness of the change handed to us by that customer.
They ignored us yelling at them.
You ignored the sight of the carcass on the side of the road.
Each of these suggest that the ignorance was on purpose, it was intended, it was active