As of right now the only way to get shortsword as favored weapons is being a drow. Can we not? this means that if you dont want to or cant be a drow and want to use shortsword you are limited to Fighter, monk(we all know ninja spy needs some work and is behind a lot of other classes), barbarian (are you really gonna use shortswords as a barb?) rogue (are you really not gonna use dagger and VKF?), bard, Ranger (not viable will use scimitar of course) and the rest of the caster classes which most will use clubs. this leaves us with Eldritch knights. most of the specs that can use them are just better to use other weapons.
I feel like this iconic weapon should have a bit more representation in the meta Maybe a "squire training" feat which could act like knights training. Maybe a new feat called Divine Training:"weapon" which would add a specific weapon as a favored weapon. Short swords are not the only weapon with extremely restrictive choice of build. picks, rapiers and greatclub are some of the weapons that have little to no place in the meta right now. Being able to decide which weapon is your favored weapon as a paladin, cleric or FVS would allow more assets of the game to be used and be overall more fun.
I feel like there are some ways to make them more popular/available without straight up buffing them
(or update the old elves models. I know it takes time and money, im just an optimistic kid.)