Not so much a project as a reference for anyone trying to use unicode characters on signs, the attached file contains a datapack with functions for creating a grid of unicode characters as a visual reference. Each character is added as 16 characters per line with the hexadecimal and integer number of the character beside it on the dark oak sign to the left. A sign can fit 16 characters of 10 pixels wide so if there are less than 16 characters then the character is wider than 10 pixels and didn't fit. Conversely if the 16 characters don't fill the width of the sign then they are less than 10 pixels wide.

Edit: Based on my calculations the sign fits about 178 pixels with a 2 pixel space between characters.

To create a grid use /function usign:u01

(u00, u01, u02.. uff)

Each function covers a range of characters in hexadecimal

ie. u20 = 2000 to 20FF

I didn't set the function to replace blocks so you need to move to create additional sets, I programmed it so that walking forward to behind the last set will create the next in a position to be viewed from the player's position.