Comparing his slashlines to Kawasaki in Japan, it looks like Toritani is comfortably a better hitter.
His career ISO is about .050 points higher and he's hit double digit homers multiple times, while Mune peaked at 4 knocks.
Toritani has been peaking as a guy that walks more than he strikes out. Mune peaked in Japan as a 2:1 K:BB guy.
Batting average similar.
Mune had more impressive SB totals, ~30 vs ~15.
Toritani's career OPS is only 0.060 points higher, but the K/BB might mean that his abilities will translate over a bit better. Kawasaki is a .240/.310/.315 true talent hitter, more or less. If Taratino can hit just .250/.330/.360 or something like that, he could approach being a somewhat average regular assuming he's a good 2B.