You can use the path to the trained data file as part of the 'Language' name-value pair. One thing to note is that the trained data file must be located in a folder named 'tessdata'. An example function call would look like this:
txt = ocr(img,'Language','path/to/tessdata/eng.traineddata');
The following documentation link provides some additional information on how to use .traineddata files with the 'ocr' function: https://www.mathworks.com/help/vision/ref/ocr.html#input_argument_namevalue_d119e140075
