Extracting sprites from sprite sheets and manually turning them into flipbooks can be quite time consuming and annoying.
A more streamlined way of using flipbooks is to prepare them in aseprite or another pixel art software and export them as JSON.
To make the entire process easier for you I started the 2D Asset Collection on patreon, which re-packs free assets by awesome creators with a JSON file for easy usage in Unreal Engine.
2D Asset Collection | Collection from Cobra Code | Patreon
I already made a video about the entire process and explain the benefits of it. But for the sake of convenience I’ll also add a write up below.
https://youtu.be/UiMUTf2kCSs?si=Ie-Vc8B7a2Pg5HU7&t=92
In the asset collection you’ll get a zip file with the entirety of the asset pack. This might only be a characters sprite sheet, but might also include props or an environment.
<aside> 💡 Make sure to unzip the file first
</aside>

You can just select all of this and drag it right into Unreal Engine. That way you might get a few error messages for the aseprite files, documents and pngs that can’t be imported, however this shouldn’t cause any issues.

You could also be more methodical about it and drag in things one by one. Any Unreal Ready spreadsheet will have a json and a png file. You’ll only have to drag the json file into Unreal Engine and it automatically knows that the png is connected to it.
<aside> ⚠️ A small number of people have problems with drag and dropping. In that case you can use the Import button on the top left of the content drawer.
</aside>

Either way this will create a Frames and Textures folder and a Sprite Sheet file in your content drawer.