-Oh, you know,- Japanese people often showcase their games on Western websites using MTL :P It's a very imperfect solution, especially for such a different language, but maybe it's worth a try?
A better option would be to find a translator and give them "a few bucks". In my region, freelancers charge $0.02-$0.05 per word, depending on their experience, so it's not a fortune, and a market like Japan could really appreciate this type of game and reimburse the costs.
As for "I'm a small fish." - It doesn't really matter. I've seen big players sharing cross-reviews with projects that didn't generate almost any views themselves. Itchio's promotion algorithms for H's simply does not exist now, so few studios are picky about such an opportunity. Besides, there's nothing stopping you from trying with other "small fish" first :P I honestly hate having my feed flooded with reviews of sloppies, but I understand that it's necessary in this environment.
(Greetings to the frustrated person from the first comment who comes here to downvote all comments <3)