I know we can restrict U-Turns but is there a way to apply a cost to Left Turns so I can ensure Left Turns are minimized?
Are you using your own data for the network dataset or are you using our routing service?
If you're using your own data (whether locally or in a service), then on the network dataset, you can set up the Turn category evaluator—ArcGIS Pro | ArcGIS Desktop in Pro or the About global turns—Help | ArcGIS Desktop (Global Turn Delay Evaluator) in ArcMap. Keep in mind that using this will alter the final cost that gets returned for the route (because it'll be adding seconds on to every turn). But it should help you avoid left turns, if you set the left turn up to have a higher delay than the other turns.
Let me know if this helps!
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