Align numbers in MS Word on exterior corners for odd and even pages
Page numbering belongs to the notorious unintuitive way that Word handles header, footer and sections.
Here is how you will be able to have your numbers align to the exterior corners, at the right for odd pages, at the left for even pages.
First define the Page Layout of your document as “different for odd and even pages,” and as “different first page.”
Then open the footer of an odd page, not the first page of that section, insert page numbering (alt+shift+p) and align it to the right.
Open the footer of an even page, again, not the first page of that section, insert page numbering and align the number to the left.