That trigger setting is the vertical resolution at which interlacing will be activated. Those patterns are probably due to a scaling mismatch. On reshade, you need to configure the scaling of the shader manually. For most ps1 games, X axis should be the horizontal resolution of your screen (2560, 1920, etc) and Y axis 240. For 1080p:
PreprocessorDefinitions=Resolution_X=1920,Resolution_Y=240
it was ok for me so better to be added in the next update