It makes conceptually no sense to have such an option! The whole point of mirrorless is you shouldn't need MFT because AF and image sensor are one and the same. You are asking for a redundant feature. Well know issue with 35mm is decentering has nothing to do with front/back focussing!
Well my Samyang is miles out at 0 (default for the lens) and at -3 its tack sharp.

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Razorbill
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The pup
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