The Japanese fleet has a bunch of these "Helicopter Destroyers" already
That is a pic of a box for a model of an earlier helicopter destroyer, the Hyuga, which is slightly smaller.
It is depicted in a 'fictional scenario', called "Operation Senkaku", defending the Senkaku Islands against "neighboring countries."
The arrow points to a sinking, burning carrier of the Chinese navy, apparently. And those are US Marine Corps V-22 Ospreys as well, so...
In any case, whether or not these ships can carry fighter jets, and are thus "aircraft carriers" instead of "Helicopter carriers", it all depends on what the scenarios are, that the Japanese navy intends them to be used. If they are intending to only be operating within range of the Japanese home islands, they would be under cover by land-based fighter jets. Maybe they don't need to carry fighters.
As a helicopter carrier, the ships would be useful in disaster relief efforts too, e.g. tsunamis.
also, as I understand things, an "Aircraft carrier", normally carries fighter jets for fleet air defence, and usually strike aircraft too, for offensive actions.