sigma 85 art vs samyang/rokinon 135 f2 comparative sharpness & image quality

Hi all! First of all, thank you for read this!

I see that nobody or almost nobody has talked about this comparison. Well, it is that I had the samyang/rokinon 135 f2 and I thought I would complement it with the sigma 85 1.4 dg hsm art for when I have less space to shoot and because of the fame of this sigma lens (I had never had the pleasure of trying it). I got an 85 art on the used market that apparently looks almost new and the lenses are pristine. Well, for example, in the comparative tool of the-digital-picture site it seems the sigma to have better sharpness, especially in the center and in lenstip site they say that the sigma at 1.4 has less resolution than the samyang at f2 but the sigma at f2 , 2.8 and 4 say it's a bit sharper. Well, I am a little worried because I have carried out numerous comparative tests (well done and conscientiously, in laboratory format and in the field) and this is not the case, in my case the samyang wins. Lenstip used a 5dmarkIII and I used a 6d mark1, the results should be similar to lenstip, but in my tests the samyang wins a little, it has a little more sharpness and micro-contrast in same apertures. My question is if someone has also been able to compare them properly or has owned both (better with 6d mark1) and if it also happens to them like me that the samyang/rokinon is a little better or not (if they differ from the comparative websites), because I have doubts if send the sigma to technical service and have them review it. The fact is the images don't look bad at the sigma and they look pretty sharp but the question is can they look any better? is it below its full performance? how to know for sure? Has anyone had both and been able to properly test and compare them? Thank you very much and any help and opinion will be very well received!