I have been to the (landside) KAL lounge in Osaka a few times, though they often claimed to be "full" and refused PP customers.

Packaged foods for the most part (onigiri, bread, cup ramen). There is a beer server and at least in the past, Ballantine's 17yr, which is a better whiskey than most business-class lounges offer.

The last few times (pre-Covid) I ended up going for the ¥3,000 credit per guest at one of the approved restaurants, which was a much better choice foodwise.