What is the C++ Equivilent of FindPlayerStart in Unreal Engine Blueprints?

What is the C++ Equivilent of FindPlayerStart in Unreal Engine Blueprints?
The function on GameModeBase is not virtual; even though it can be overridden in blueprints.
Lots of older examples from around 4.3 seem to suggest there is a FindPlayerStart_Implementation function but I can’t find it in 4.19.
How can I achieve the same behavior as overriding FindPlayerStart and returning my own PlayerStart Actor in a blueprint?