[TOnlineResult](API\Plugins\OnlineServicesInterface\Online\TOnlineResult)< [FLobbyClientDataPrepareClientChanges](API\Plugins\OnlineServicesCommon\Online\FLobbyClientDataPrepareClientCha-) > PrepareClientChanges ( [FLobbyClientDataPrepareClientChanges::Params](API\Plugins\OnlineServicesCommon\Online\FLobbyClientDataPrepareClientCha-\Params) && Params ) const