How to effectively feed my sleepy newborn?

My baby girl was born exactly 2 weeks ago at 9 lbs 10 oz. I didn't have gestational diabetes or anything - she was just big. She lost a good bit of weight after delivery and got down to 8 lbs 15 oz. Today she is 9 lbs 8.5 oz. It's been the full 2 weeks since delivery and she isn't yet at her birth weight.

I've been seeing an IBCLC and a very pro breastfeeding pediatrician. No one is telling me to supplement yet, but she is definitely borderline. Her 2 week appointment with the pediatrician isn't until Monday, so she will be at birth weight by then at least. But today at the IBCLC, she wasn't quite there. We did a weighted feed and she took just over 2 oz, but it was a struggle.

She just keeps falling asleep. I have to do tons of breast compressions to remind her to keep nursing. She will be wide awake and aggressively rooting, but 5 minutes into a feed it's like my breast milk is a sleeping pill and she starts dozing off. She only wakes up when she's off the breast. Her best sleeps are when I let her stay latched long after she's stopped sucking - like 15-30 minutes after the feed has effectively ended. Sometimes she falls off the breast and just has a mouth full of milk that just dribbles out of her unconscious little mouth.

I know her slowish weight gain is not a supply issue. I've incorporated a bit of pumping here and there and in a 10 minute session immediately following a feed, I consistently get 2 ounces. She's has a couple nursing sessions where she's wide awake and it's just continuous suck and swallow. But her norm is sleepy baby. I almost always nurse her naked and we do lots of skin to skin. I try all the tickling and blowing on her face tricks, but breast compressions have been the most effective. Even so, she's very slow.

I just don't know if this is something she'll grow out of or if there is some way to make her have a bit more energy come mealtimes.