“Will it mess my daughter up if I got her a baby ear piercing? Like is that a problem with consent?”

No, you won’t mess your baby if you pierce her ears and it is totally up to you (and your co-parent) whether to pierce her ears. The only important thing is that the piercing is performed with sterile equipment by a qualified professional and that you follow the instructions they will give you to prevent infections.
I hope this information helps! I wish you and your baby all the very best.
Love,
Ana