Anyone know which templates reduce int?
You don't need templates to achieve maximum idiocy.
Bakemono (Oriental Adventures, p146) were given LA +0 in the 3.5 update (Dragon 318, p44). The update also changes the entry from humanoid 1 to warrior 1. They seem to have applied an ability array, but they don't note what the abilities were before racial adjustments.
You could assume the old adjustments still apply: +4 str, +2 con, -8 int, -4 cha. In that case the original ability scores were str 11, dex 11, con 12, int 10, wis 9, cha 8. That doesn't quite match the non-elite array; one of those 11s should be a 13.
Alternately, you could assume they applied the non-elite array in the same way as all the other warrior 1s in monster manuals: str 13, dex 11, con 12, int 10, wis 9, cha 8. In that case, the new ability adjustments are +2 str, +2 con, -8 int, -4 cha.
In either case, you get +6 natural armor, a 30-foot land speed, and small size.
(hazy) Isn't there a rule that if your Intelligence
is less than 3, it gets bumped back up to 3 ??
There's some stuff on pages 172 and 173 of the Dungeon Master's Guide that gives player characters higher ability scores than normal when combining low rolls and racial penalties. It's especially pronounced for intelligence.