About Sandro, according to those pics I saw here, his head shape needs improvements - I didn't see him in game but according to previews from Blender I saw that model is not quite similar to his real one.
His jaw sides (I mean sides of his face) is too square. looked some his photos and he has mode rounder sides of his face, also jaw looks to massive according to other his face, too wide, maybe try to make it more smaller.
His face is wide at cheekbones line if you noticed but than face is narrowed to the chin and also make smaller jaw because too wider and massive, smooth sides of his face - make them not square but more rounder, also don't like eyes, they look too big and also you made not quite good their shape - try to raise up corners of each eyes don't know how to write it in English but try to explain, half of the eye that near to nose is right but other part is too low just raise it up, make it with both eyes, also eyebrows raise up, because his eyebrows are not straight - they are more likely triangle shape, also his forehead is too wide, I mean sides where forehead is going into hairline shouldn't be so wide, just ad some hair at tex or just make them thinner at model, think that's all.
And also try to post some screens from game to better understand how faces look in FIFA.
Text looks really good, expression not bad but don't like head shape a lot, about Sigurdsson - don't know him so can tell nothing.
Try to work better at head shapes because textures are really good but models need some fixes, wrote a lot, hope you or online translator can explain you what I wrote here and I hope my advices will help you.
And for the future - post at least one screen from game to better understand how face looks.
how about some faces from steaua fc...ajax and chelsea killer 
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