@amandak695 Pediatric Medical Assistant here (8 years & counting) and mama of two breastfed boys (2year old and 3 month old). I may have some medical knowledge but this is just my insight and personal experience.
I cosleep/bedshare with my kids.
I weaned my 2 year old from night feedings when he was 15 months old mainly in preparation for new baby. At this age, I knew he was sufficiently eating solids during the day and he was "feeding" for comfort and I didn't oppose. He transitioned as to a toddler bed as difficult as one would expect any kid going into a new environment. I dont expect to be doing anything different with my current infant.
I think what you offer during the day is wonderful and most definitely KEEP offering! Heck, offer everything and anything! Once babies start moving and grooving, it is TOTALLY normal to see weights plateau from the curve. Dips aren't normal unless they are sick.
Have you thought about maybe asking for a referral for a pediatric occupational therapist? They can help with strengthening oral motor skills needed for solid food intake! Could be a more helpful route rather than stopping night feeds altogether in hopes it would "make" your baby eat more solids during the day, especially if this isn't something you want to do.
Also, if you did stop night feeds, your body would only adjust to not produce as much milk at night - it shouldn't affect your day feeds