A France-only war did not rescue German cruiser policy

Would German cruiser policy have made strategic sense in a war against France without British participation?

Not convincingly. France possessed a substantial cruiser force, greater ability to answer German construction, and fast capital ships that Germany still had to respect.

German cruiser policy would still make little sense if Berlin expected war with France while Britain remained neutral. The Marine Nationale already had a cruiser force and could outbuild Germany in that category. Italian participation might improve the balance after 1939, but French fast, heavily armed capital ships would still complicate the German position.