This is a weird one because I can't find why these are listed as free, but can confirm Akuto Showdown and Coffee Crisis were free for me.
Others have reported One Strike and Akane are free as well. Only way to see for sure is to click each linkw Holst signed into your Nintendo Account of search for "QubicGames" through the eshop on your Switch console
Update:
This is part of their fighting weekend
https://www.facebook.com/QubicGames/photos/a.240882051093/10…They have a regular sale on games for free if you own one of their games, another coming up in December >https://www.wepc.com/news/qubicgames-free-games/
Thanks. I've amassed quite a lot of these QubicGames for free, and am yet to play any. Maybe one day!