Hi there,
I believe you should take some time to expose your pics, they seem to be a bit overexposed, take your time, educate the eye to look for the medium light conditions in your composition, no light, no shadow, just the middle point, expose there. Hold your camera steady (better use a tripod, ) below 5,6 aperture and lower than 1/100 unless you have a very firm arms, you will always find your shots a bit blured, even though you edit raw after. Work out your white balance settings, in such sunny conditions the auto mode can go bannanas, set your lowest Iso, and why not use the bracketing settings, on jpg for a test, you will easily download those and you will see the amazing results your equipment can deliver. I do not sincerely think the issue is with the lense.
Good luck
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