I agree with dr.Mirna Leko-Šimić and dr. Karl Pfeiffer said
The differences in scientific disciplines, methods of scientific research and the availability of technology may prevent this from happening and will therefore affect the results of the evaluation and be unrealistic.
The idea I think is now present in RG but it can succeed at the level of one country
For many reasons, including the difference of education systems from one country to another the curricula vary from country to country and also different disciplines, etc
I do not think this is possible, because of the different academic visions among the countries of the world and the overlap of the evaluation process with the activities of different universities, which means that it is impossible to achieve this.
I believe the most difficult part would be the differences between the various country cultures and the resulting weightings given to the categories used for the assessment. Frankly that is difficult enough within my own University and even within my College.