fastest way to call a function in another script by name

What’s the fastest way to call a function in another script if I am only given the name of the function as a string and the arguments as another string.

SendMessage does the job but some posts say it is slower than pure C# methods. I may want the communication to occur every update. Is there a faster C# solution besides SendMessage?

I want to add this to a C# plugin script. I am just learning C#.

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