The following 9-by-8 French word rectangle attributed to Jean-Charles Meyrignac appears on the Internet (for example, on www.mathpuzzle.com for May 25 2004). The source says that all but one of the words can be found in the Petit Larousse. This is intermediate in difficulty between an 8-by-8 and a 9-by-9 double word square, the latter of which has never been done in English. No 9-by-8 English rectangles are known by us to exist, but French is particularly adaptable to this form because of the many inflected verb forms.
Eckler, A. Ross
"A Near-Perfect French 9-by-8 Word Rectangle,"
Word Ways: Vol. 40
, Article 17.
Available at: https://digitalcommons.butler.edu/wordways/vol40/iss4/17