every phone has wakelocks,a more useful graph is the battery usage one.
messenger is known for draining battery since it ignores wakelock values ( it goes through despite phone sleeping,just like sms or a call) so it sometimes checks if there are new messages,waking up the device.
about the sync services,try disabling syncing in flyme account settings,or just uninstall them completely.
one weird thing i’ve noticed is that ever since i tested something out for a user ( if alam goes through in super battery saver mode ) both the calendar and clock app waked the phone app like x300 times. super weird and stupid. and the phone not draining battery overnight is because you’re not moving the phone,so the carrier towers stop pinging your phone for signal strength so often,since it’s always at the previous location. while you’re out at school/work you’re moving the phone so different towers ping at different times, using the phone battery more.
tl;dr poor battery optimization from messenger + flyme. is perfectly normal for such heavy customized rom with a lot of useless tiny features. :( sorry if this is lengthy and messy but i really hope i cleared some confusion out.