Loading UMG UI from c++ plugin

Hello, I’m new to ue, and would like to develop a plugin for terrain mesh creation.
I was thinking about designing the plugin ui via a user widget blueprint, but I’m not able to load it in OnSpawnPluginTab, is it possible?

This :
UUserWidget* widget = (UUserWidget*)StaticLoadObject(UUserWidget::StaticClass(), nullptr, TEXT("WidgetBlueprint'/IGNDataLoader/UI.UI'"));

give null and an error in the log :

LogUObjectGlobals: Warning: Failed to find object ‘UserWidget /IGNDataLoader/UI.UI’