I have stewed sardines in Sake and soysauce based mixture with homemade Úmébóshí/ homemade traditional Japanese pickles of apricot and gingers cut into strips.
They were yummy.
The reason why we put ginger and Úmébóshí is to eliminate the fishy smell. Also citric acid in the Úmébóshí helps the absorption of the calcium into the body.