If you want to centralize all your gaming accounts, Minimap is a great option. The service aggregates game accounts on Steam, PlayStation, Xbox and the Epic Store so you can monitor progress, achievements and friends in one place. It also offers personalized game recommendations, a community of gamers and a free version to get you started.
Another option worth a look is AppManager. Although it's geared more toward managing user and app subscriptions across different services, its centralized management abilities could be useful for your gaming needs. It consolidates your subscriptions, tracks your spending and aggregates invoices so you can better keep track of your gaming expenses.