TOKYO—Nintendo Co. is encouraging some producers of violent or risqué videogames to provide content for its Switch console in an attempt to shed its image as a maker of devices just for families, software developers say.

This isn’t the first time games for mature audiences have been available on Nintendo systems—Switch predecessors such as the Wii U had them. But in recent years, the company has been mostly elbowed out of that market by Sony Corp.’s PlayStation and Microsoft Corp.’s Xbox.

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