Async Loading Screen is a free and open-source plugin for Unreal Engine. Async Loading Screen allows you to easily configure a Loading Screen System in the project settings, and automatically add a Loading Screen whenever you open a new level, without Level Streaming.
The subj.
https://github.com/truong-bui/AsyncLoadingScreen/blob/b984d1900aa97c5a60d6411e69412ecda064e296/Source/AsyncLoadingScreen/Public/SLoadingWidget.h#L27