Looking more into this, it seems Tatsuya Nishimura was a sound effects designer at Capcom. Sakaguchi, Nishimura, Abe, and Shimomura were credited as responsible for the sound design of the Super Nintendo version of The World Warrior. These were super-condensed credits with no separate composition credits, but the music reused the Arcade version of the game. Sakaguchi and Nishimura were actually sound programmer and sound effects designer respectively as confirmed by the more elaborate credits for Street Fighter II Turbo.
The limitations of the original credits extend beyond crediting true sound designers as composers. Super Street Fighter II Turbo contained new tracks mainly created for the five new characters. The reliable Arcade-History and MobyGames both credit Syun Nishigaki and Isao Abe as being responsible for the music. Isao Abe's role includes both new compositions and reprises; if his contribution were only reprises, Yoko Shimomura (who is confirmed in several albums to have confirmed all the character themes but Abe's Sagat) would have been credited too.
I'm pretty sure that SNESMusic was the original source of the album composition credit given their SPC set is over five years old and they misspell Tatsuya Nishimura as Tetsuya Nishimura. Not a good idea to use SNESMusic as the source since the score is from the Arcade game not the Super Nintendo port. The Super was to show the game was awesome not to show it would eventually by destined for the Super Nintendo.
Besides Nobuo Ouchi and Toshio Kajino were the sound designers this time.
And that solved, I change the credit to 'Yoko Shimomura, Isao Abe, Syun Nishigaki'.