(Not Recommended anymore, because there are many errors nowadays with this old tool)
Solution 1: Get the newer Warcraft 3 Assistant to change the WC3 version, 2019 Edition.And in contrary for the normal BNet ladder of course you need the newest Warcraft 3 patch! With the Warcraft 3 Version Switcher you can quickly change the Warcraft 3 patch version! Some Wc3 platforms like W3Arena or Gameranger require an older more stable patch than the newest.