The reticle on 4x scopes are not canted (slanted) like the 2.5x Type 97 scopes, so if this one is, it's because the inside etched glass has gotten rotated slightly.
You have to remember that the T-97 snipers (which used the 2.5x10 power scopes) were in service for several years before production of the 99 sniper program began in 1942 at the Kokura Arsenal. With the 4x scope not yet ready for production, the first 99 snipers were made at the Kokura Arsenal, all were mounted with the 2.5x scopes. Kokura 99 snipers coincided with the 22nd-early 23rd series production through late '42, early '43. After approximately 1000 rifles made, the Kokura Arsenal quit making snipers and remaining inventory of 2.5 power scopes were sent to the Nagoya Arsenal which were now into production using the new 4x scopes. The 2000 +/- scopes were used in the 5000-7000 serial range by relieving a rear portion of the larger 4 power scope mount to accommodate the smaller scope base of the 2.5x scope. Collectors refer to these rifles as "cutbacks". When the left over 2.5x scopes were used up, the 4x scope resumed at about the 7000 serial range.