Microtransactions in Predecessor are summarized as...

The game features two currencies, one is earned by playing, and the other is a Premium currency (Platinum) that can only be purchased. The Premium currency needs to be purchased in bundles. None of these bundles match any of the store item prices.

The game features many playable heroes. Some of these are free, others are available on timed rotations, and others need to be purchased. These can all be purchased with both currencies, free and premium. The price of heroes varies quite a lot. Some cost 1000 Platinum, roughly equal to 10 USD, while others cost 200 Platinum, roughly equal to 2 USD.
Instead of purchasing the hero directly, you can opt to buy them in bundles. Some of these bundles are timed exclusives. These bundles contain extra cosmetics like sprays or character skins, or multiple heroes in one go.

Each hero has a number of cosmetics. This includes skins, banners, titles, and borders. Some of these can be earned for free by leveling up each character through a system called Affinity. Each Affinity has a free track and a premium track; the premium track can be purchased for 500 Platinum, equal to roughly 5 USD.

Skins are available in the store at all times. Their prices range from 500 Platinum to 1600 Platinum.

Next to the in-game store, you can also buy bundles through Steam. There are 3 bundles: Rare, Epic, and Legendary. Costing roughly 20 USD, 50 USD, and 80 USD respectively. Each bundle unlocks all 29 heroes, with each higher tier only unlocking additional cosmetics and Premium currency in larger volumes.

Premium currencies come in quantities that do not match the price of regular shop items, forcing you to spend more for less.
Includes a limited-time always rotating store with exclusive discounts and/or cosmetics.
Contains premium currencies that can only, or almost exclusively, be purchased with real money.
Features unique cosmetic rewards for pre-ordering the game.
Free to play. Requires no up front payment.