Open up all the .osu's inside the folder. Now highlight all the [TimingPoints] text and everything below it before the line break and insert this:
[TimingPoints]
11729,333.555703802535,4,1,0,50,1,0
13063,333.555703802535,3,1,0,50,1,0
16065,333.555703802535,4,1,0,50,1,0
25404,333.555703802535,3,1,0,50,1,0
28406,333.555703802535,4,1,0,50,1,0
38412,333.555703802535,4,1,0,50,1,0
71767,333.555703802535,5,1,0,50,1,0
73434,333.555703802535,4,1,0,50,1,0
76770,333.555703802535,4,1,0,50,1,0
87443,-100,4,1,0,50,0,1
95449,333.555703802535,3,1,0,50,1,1
98451,333.555703802535,4,1,0,50,1,0
102453,333.555703802535,5,1,0,50,1,0
104120,333.555703802535,4,1,0,50,1,1
114793,-100,4,1,0,50,0,0
116128,333.555703802535,5,1,0,50,1,0
117795,333.555703802535,4,1,0,50,1,0
121130,333.555703802535,4,1,0,50,1,0
122464,333.555703802535,3,1,0,50,1,0
125466,333.555703802535,4,1,0,50,1,0
134805,333.555703802535,3,1,0,50,1,0
135805,333.555703802535,5,1,0,50,1,0
137472,333.555703802535,3,1,0,50,1,0
138472,333.555703802535,4,1,0,50,1,0
e.g.
What it was before:
[TimingPoints]
6070,333.555703802535,4,1,0,50,1,0
87457,-100,4,1,0,50,0,1
98464,-100,4,1,0,50,0,0
104135,-100,4,1,0,50,0,1
114809,-100,4,1,0,50,0,0
What it should be now:
[TimingPoints]
11729,333.555703802535,4,1,0,50,1,0
13063,333.555703802535,3,1,0,50,1,0
16065,333.555703802535,4,1,0,50,1,0
25404,333.555703802535,3,1,0,50,1,0
28406,333.555703802535,4,1,0,50,1,0
38412,333.555703802535,4,1,0,50,1,0
71767,333.555703802535,5,1,0,50,1,0
73434,333.555703802535,4,1,0,50,1,0
76770,333.555703802535,4,1,0,50,1,0
87443,-100,4,1,0,50,0,1
95449,333.555703802535,3,1,0,50,1,1
98451,333.555703802535,4,1,0,50,1,0
102453,333.555703802535,5,1,0,50,1,0
104120,333.555703802535,4,1,0,50,1,1
114793,-100,4,1,0,50,0,0
116128,333.555703802535,5,1,0,50,1,0
117795,333.555703802535,4,1,0,50,1,0
121130,333.555703802535,4,1,0,50,1,0
122464,333.555703802535,3,1,0,50,1,0
125466,333.555703802535,4,1,0,50,1,0
134805,333.555703802535,3,1,0,50,1,0
135805,333.555703802535,5,1,0,50,1,0
137472,333.555703802535,3,1,0,50,1,0
138472,333.555703802535,4,1,0,50,1,0
Next, go back into osu!edit and in the Timing Setup Panel, check "Snap to New Timing", then "Use Snap Divisor of 1/8", press OK... then good luck moving back ALL the 1/6 notes. (yes that means you'll have to skim through the entire maps AGAIN just to fix the notes.)
Why the sudden million offsets, you ask? Well see, this song uses a lot of 3/4, 4/4, and 5/4. To keep it as Taiko-authentic as possible, all barlines must land on their appropriate space. So you have to do this with all 8 maps.
Good luck with all the 1/6s. ._. I hate Tenjiku.