Microtransactions in Fall Guys are summarized as...
Fall Guys has recently gone free-to-play. With this the game was removed from Steam and on PC is only available via the Epic Games store.
With the change to free-to-play they moved from most cosmetics being earn-able from regular play, to a model where you will need to purchase Premium Currencies in order to buy skins. These Premium Currencies in come quantities that often don't match the price of regular shop items. Most items are not available at any time and instead are only available at given times in an always rotating store. There still is an in-game earn-able currency that allows you to buy some skins, but these skins are often also only available in a limited time store.
Fall Guys also features a premium Battle Pass. Battle Pass levels can be purchased with the Premium Currency.