Just what the title says.

"All Chapters" includes every a, b, and c side for chapters 1-8 as well as farewell.

"True ending" simply involves unlocking and completing farewell, which doesn't require b-sides or c-sides, although players will sometimes route 5b and 6b into runs because they're faster and also collect 2 of the 4 hearts needed for getting into core.

The heart gate in chapter 9 is skippable so the B-sides and extra crystal hearts are unnecessary, but the gate in core is not skippable so you still need 4 crystal hearts (plus obv the one at the end of core to unlock chapter 9).