Is there a way to transpose a sprite sheet or have a sheet be spliced top to bottom instead of left to right?

I have a sprite sheet of over 2000 emojis which are inserted top to bottom in order of their Unicode value. I did not make the sheet so I can not remake a sheet going left to right as Unity reads in sprite sheets by default. Is there an easy way to create a transposed sheet (swapping rows/columns) or for Unity to read in the sheet top to bottom instead of the current left to right? Or by some chance does anyone here have access to every emoji sprite individually that can make a new sprite sheet? Here is a link to a reference to the sheet I am using: https://github.com/iamcal/emoji-data/blob/master/sheet_apple_16.png

Any help would be appreciated. Thanks!