Previous Pokemon games had an EXP Share item to level up all your Pokemon in your party which made things quite a bit easier.
About EXP Share
In the very first generation of Pokémon games, the only way for a Pokémon to receive any experience points was for them to participate in a battle. Old school players had to spend a lot of time battling with each Pokémon if they wanted them to level up.
It also made it very hard to keep all your Pokémon equally leveled up as you journeyed.
EXP share item
Starting with Gen 2, we finally got the Exp. Share item. This was a held item; when held by a specific Pokémon, it allowed the six Pokémon within your party to share the experience points obtained through a battle, regardless if they fought at all. In Gen 6 and Gen 7, Exp. Share turned into a Key Item, which meant that it applied to the Pokémon in your party without anyone needing to hold it.
Players could turn Exp. Share on or off within the game menu.
Now in Gen 8, Exp. Share will no longer be a Key Item. Players will have the benefit of equally shared experience points distributed among any members of their party whether or not that Pokémon participated in the battle.
Auto EXP share
Speaking to Game Informer magazine, Pokemon Sword & Shield director Shigeru Ohmori revealed that EXP Share is no more and that Pokemon in your party will now level up automatically. There’s no word on whether this can be turned off for those who want the extra challenge. But undoubtedly, there will be some players who want a more intense gaming experience and would prefer to play without it.
