I need a way to override this ERR list with customized messages depending on the error that occurred.
Update question
This happen when my api failed.
You could use the localisation feature and rewrite that single translation with your own or use the getLocaleText
function (https://www.ag-grid.com/react-data-grid/localisation/):
export const AG_GRID_LOCALE = {
loadingError: 'Custom error message'
};