British 9.2-inch cruisers force Germany beyond the pocket battleship

Would British eight-gun 9.2-inch cruisers make the Deutschland-class concept obsolete before construction?

Yes; Germany would need an 11-inch ship closer to Scharnhorst in order to fight the new cruiser standard.

A British class built in 1919 would likely set the later treaty benchmark and make 9.2-inch guns common among foreign heavy cruisers. Six 11-inch guns would then be an inadequate answer to an opponent firing eight faster 9.2-inch weapons. Germany might describe its response as a coastal battleship for political reasons, but the fighting requirement pushes toward a larger Scharnhorst-like ship. The counterfactual shows how one early cruiser choice can move the minimum viable armament for every navy that follows.