I gather you are wanting a zigzag to treadle. Yes, the 237 manual shows the Treadle Drive.
There are some electric Necchi machines that have a plugs in the bed to be removed so that it can be treadled. Supposedly the SuperNova is one that might. My SuperNova does not have the plugs. There a couple of more modern Necchi machines that can be treadled.
Glenn's Fishy Quilt - The blocks and the machines
Necchi Supernova
I need help rewiring a pedal to my old Necchi
I haven't paid much attention to Bernina machines, but did find a couple that can be treadled.
My treadle conversion
Bernina 740 Favorit treadle
I don't remember for sure if the serger that CD put in a treadle actually worked very well, but there is a picture at
MUTT (Multi-Use Traveling Treadle)
Janey - Neat people never make the exciting discoveries I do.