Aw...those jammies are so adorable...what a little doll baby Luma is
Love the tutu's, they are so pretty. Yes, you can hand stitch the sew on velcro. Hot glue would just crack off of material when the fabric was flexed, I believe. I'm with Amyee, not a fan of stick on velcro. Sewing would likely be the best option.
Oh, when sewing on...it's hard to poke a needle through...but it can be done.