Explanational

[Sommer]

often mistaked for explainable
used by people in [essays] for [some strange] [reason]

[engladNak]

The word explanational is not a common English word and is often mistakenly used in place of explanatory. Explanatory means serving to explain or clarify something. It is possible that people use explanational thinking it means the same as explanatory, but it is not a recognized word in the English language.