I don’t know if this should work like this. Quickly searched the forum and didn’t find a post.
In raid after JF’s Special I attacked with Mist’s special. The heroes got protected against the defence reduction of special skills but they didn’t get the defence buff.
Mist special prevents them from getting new buffs, Jf flips her defense down against special to a buff but her special blocks the buff so neither the def down or the def buff are applied.