games: state => state.games,

  gamesNames: state => {
            let games = []
            for (let g of state.games) games.push(g.name)
            return games
        }


to działa



 fortniteList:  state => state.fortniteList,

  fortniteListKD:  state => {
            let fortniteList = []
            for (let g of state.fortniteList) fortniteList.push(g.kdList)
            return fortniteList
  }

a to nie