In a sense, the items here could be considered “Customs” as they aren’t officially licensed. The big difference though is these are often made by a company mass-producing them over a Small Business Seller or even one-person team. They often draw the line between “Custom” and “Official” as while they are not official, they go through a lot of the methods something official would on its way to market thus this Third Party section.
Mega Audino Bootleg Plush by OlyFactory
Mega Audino Zukan by 魔盒工坊
Pikachu & Mega Audino Commemorative Edition Card
Tag Cosplay Card by Tag Team
Mega Audino Scale World Figure by Pokemon Dream Studio
2020 Mega Audino Pokedex Edition Card by San Jose Publishing