That could be due to genetics or it could be a bacteria phytoplasma spread by chewers like leafhoppers.
Look closely at the leaves and bud sites for deformities. A couple of your pics look normal and healthy, but the third and fourth pics look suspect.
Edited to add - they will grow out of it but Ive found the bud sites dont grow as healthy as the nonaffected sites. For years I assumed it was just one of those things that happens with outdoor grows as the temps dip and the heavy rains come...until I took clones from an outdoor plant and watched it spread inside to all the other cuts under a dome in the same tray. (sometimes I take cuts from plants outside as a way to revive old genetics. I've learned I need to be much more careful)
Then I found this thread and it made sense.
Dark Purple Disease Affecting New Growth? | THCFarmer
Read the whole thread. You gotta get past all the arguing to get to the real meat and potatos info. Or google Gnarly Death cannabis