Unable to create custom python class that extends MoviePipelineVideoOutputBase

Similar to this tutorial which creates a custom class that extends the MoviePipelinePythonHostExecutor:

@unreal.uclass()
class MoviePipelineMyCustomEditorRenderExecutor (unreal.MoviePipelinePythonHostExecutor):
    @unreal.ufunction(override=True)
    def execute_delayed(self, dummy_queue_ignore):
        ...

I want to create a custom class that extends MoviePipelineVideoOutputBase like this in UE5.2:

@unreal.uclass()
class MoviePipelineMyCustomVideoOutput(unreal.MoviePipelineVideoOutputBase):
    @unreal.ufunction(override=True)
    def is_audio_supported(self):
        return False
    # ...

Unfortunately I can’t get past even implementing this super simple is_audio_supported function:

Exception: generate_class: Failed to generate an Unreal class for the Python type 'MoviePipelineMyCustomVideoOutput'
Exception: MoviePipelineMyCustomVideoOutput: Method 'is_audio_supported' was set to 'override', but no method was found to override

If I remove the function or the @unreal.ufunction annotation it complains that its not implemented (which makes sense):

LowLevelFatalError [File:../Plugins/MovieScene/MovieRenderPipeline/Source/MovieRenderPipelineCore/Public/MoviePipelineVideoOutputBase.h] [Line: 87] 
Pure virtual not implemented (UMoviePipelineVideoOutputBase::IsAudioSupported)

But no matter what I try to put into @unreal.ufunction(...) nothing works. I tried all combinations of static, getter, pure, virtual, override that I can think off and nothing works.

I am now trying to instead implement it C++, but I would prefer to use python. Any help is appreciated.

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