please help me find this manga

mc is reincarnated (i think) but i know the setting is historical/fantasy. mc is probably in a duchal family. all the characters go to school and i remember her being a wizard of yggdrisil (i forgot spelling). she gets tricked by a hallucination of a child she made up and they all end up fighting this lady who wanted mcs powers. if anyone can help me find this i appreciate it, i've been trying to build my lists again with stuff i like