So this is what I've been able to gather from this situation. Some of this is just speculation though.
Office Create is the developer of this Cooking Mama Cookstar release. Planet Entertainment licensed / published the game only for the Switch in Europe, Australia and America.
Both companies were making their own version of the game though but Planet Entertainment was in charge of the main product with Office Creative overseeing the project. The game was set to release but Planet Ent did not like the changes made to the game and poor quality of it so they did not authorize a release. Office Creative said

that and released the game anyways without authorization. This means they released it to retail stores and online digital shops.
Planet Ent is like "WTF is this shit" and likely sent cease and desist letters to all major retailers selling the game as they are now suing Office Creative for illegally releasing a game outside of their contract. This is why it was taken off the eShop and removed from all U.S. store shelves (Walmart, Target, Gamestop and Best Buy).
The eBay sellers are distributors for major companies (mainly Walmart). After the game was pulled, they probably had no choice but to sell the game on their eBay stores to clear stock as no store wants the game anymore.
As for Office Creative (who just sold the game on their site) is liking trying to recoup their loses from the game as it is an incomplete mess (based on several major reviews). They need to pay their employees and bills so they took the risk. They rather deal with the legal repercussions afterwards than have lose their studio (which will likely happen anyways at this point).
Doesn't help that Planet Ent did not authorize a release of the game in Europe for the PS4 but Planet Ent is advertising the game as such in Europe. This is bad because Planet Ent published the game but they did not publish it for the PS4 or in other markets which puts them in legal issues as well as their name is attached to the project.
This game is a bit mess for the gaming community and we are likely going to see a big legal battle for this.