longwise vs lengthways

longwise is not an adjective while lengthways is an adjective.

Word	Noun	Adjective	Verb	Adverb
longwise	No	No	No	Yes
lengthways	No	Yes	No	Yes

As adverbs, longwise and lengthways are synonyms defined as:

Other synonyms of longwise include lengthwise, longitudinally, longways.

longwise (adjective)	lengthways (adjective)
	running or extending in the direction of the length of a thing

longwise (adverb)	lengthways (adverb)
in the direction of the length	in the direction of the length