The variant Everelda is used a fair amount in Yorkshire in the north of England especially in the Victorian period and before. I happen to think it’s s lovely Anglo-Saxon name.
I really really love the more rare names and somewhat dislike the popular names because they are over used and don't seem special to me so Everild is a beautiful name to me but am having second thoughts about it so I most likely wont use it but if you are expecting and like this name you should definitely use it! :)