You'd get a very dull thick sound. You'd be sensing along a fairly long section of string, so you'd have a lot of comb filtering as a result. A lot of the higher harmonics would get cancelled out, or severely reduced in level compared to a normal orientation. So the lower harmonics would predominate. Rather like turning the tone control down by quite a way.

And the effect of 6 magnets on a single string (plus contributions from adjacent pickups) would result in a lot of string pull, so that the pickups would have to be set very low to avoid horrendous wolf tones.

If you summed the outputs, rather than took each string to a different output, then it wouldn't really be much different to having six normal orientation thin single coil pickups arranged next to each other.