Hello there,
There is no script currently available that must once be enabled this feature will not disable at every restart.
We can measure the effect of Efficiency mode on the foreground experience by comparing the completion times when the system is loaded with the CPU load without Efficiency mode applied vs. when the system is loaded with Efficiency mode applied to the CPU workload. Both normalized to the baseline completion times without the CPU load. https://devblogs.microsoft.com/performance-diagnostics/reduce-process-interference-with-task-manager-efficiency-mode/
Hope this resolves your Query !!
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