You can try to avoid generation of emxArray types in the DLL by not relying on variable size arrays. This will result in generation primitive types like double arrays, which you can interface with C#.
To avoid using variable-size arrays, you can change the config settings related to Dynamic Memory Allocation. for this, you can use coder.EmbeddedCodeConfig
Option 1: Set the DynamicMemoryAllocation property to Off to disable variable-size arrays for all arrays in your code
Option 2: By default, DynamicMemoryAllocation is set to Threshold, and you can adjust the threhold value to something within which your array will not use variable-size. To do this, you can use the property DynamicMemoryAllocationThreshold (default vaue is 65536).
You can look at examples in https://www.mathworks.com/help/coder/ug/use-c-arrays-in-the-generated-function-interfaces.html to see how to generate the C function interface using primitive types instead of emxArrays.
To avoid generation rtString type, you can specify your string inputs during code generation as a character vector.
