you don't have to use the entire url with the title written out on it.
For example, opening this thread gets you this url: https://boards.na.leagueoflegends.com/en/c/site-feedback/cEHhFmBr-league-url-shortener
however, you can shorten it down to this: https://boards.na.leagueoflegends.com/en/c/site-feedback/cEHhFmBr
the cEHhFmBr is like the thread's ID, eerything before is just the address for the boards on league's site. Everything after the ID is not needed
an alternative method could be to use Tinyurl to shorten it down to a very short url and share it that way, though people won't know what it is they're being redirected to pretty much until after they click it.