let array = [
[
[[534, 75665], 232, 3232],
[54, 23234, 43456]
],
[
[346, "", 3456],
[33434, 45, 345]
],
[
[436, 346, 634],
[64334, 63464, 232]
]
];
let array = [
[[534, 75665, 346, 436], [232, "", 346], [3232, 3456, 634]],
[[54, 33434, 64334], [23234, 45, 63464], [43456, 345, 232]]
]
array.reduce((acc, el) => {
el.forEach((n, i) => {
acc[i] ||= [];
n.forEach((m, j) => (acc[i][j] = acc[i][j] || []).push(...[].concat(m)));
});
return acc;
}, [])