The Goddess Of Birth - if you load the game while doing the mystery the quest giver will reset to initial possition while refusing to speak to the player again. I was stuck in combat while the game autosaved after one fight so I reloaded the game and now I am unable to proceed with this mystery. I have tried everything - changing graphics, luring enemies near her, finishing more mysteries before comming back, restarting game ... nothing helped and it is currently the only collectible in region I have to do
More info - I was stuck after taking her up the hill while the next prompt was to speak with her. Sadly I was attacked by zelot nearby and even after killing him I was somehow still in combat
Banshee - the mystery doesn't start if it isn't the last mystery in the region.
Edit 1 for The Goddess Of Birth - World event cannot be completed due to various actions. Workaround: To reset, fast travel to a different location and return later to restart. -> this didn't work. I have finished 3 regions in between and I am still unable to talk to her. She doesn't even have a monologue while getting nearby and just stands there in silence