Hi @Romas Beinoras,
It appears that there is currently no way to only disable autocorrect and spell check for the comment section only. This is by design from Microsoft side. You can consider using the good ole Command+Z to Undo the correction when it is made.
Also, You can use File> Feedback in the Word menu to plead your case. Or you can raise a thread in the Office Word feedback portal: https://feedbackportal.microsoft.com/feedback/forum/fb6d67e3-301c-ec11-b6e7-0022481f8472You won't get a personal reply but responsible suggestions/requests go directly to the development team for consideration.
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