For LR, cable will be SMF, MPO-24F, female to female, Key up to Key down, crossover, APC to APC
For SR, cable will be MMF, MPO-24F, female to female, Key up to Key down, crossover, UPC to UPC
Note: it would be the same cable for router to router connection.
The crossover is from A to B, but the fibers 1-12 on each row are not crossed, i.e. A-1 to B1, etc, not A-1 to B-12. As fibers 1-12 are not crossed, the connectors would be key up to key down. See illustration:
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