Use APKPure App
Get Custom Themes Installer for OneUI Pie *ALL* old version APK for Android
모든 삼성 Galaxy Pie 기기에 맞춤 테마를 설치하고 사용하는 앱
You can use custom themes on your OneUI Pie without any trial limit
Supported and Tested Devices
S10/S10+/S10E/S9/S9+/Note9/S8/S8+/Note8/Note FE/S7E(NFE ROM) and all J/A series running Android Pie
The step guide is in the app itself. It has been designed for easy use and setup