I can't say I've seen this but the name of the game for babies is usually "if it's weird then it's probably normal." Our doctor said the only times to really be concerned is if they haven't pooped for 3 days, if the poop is red or if it's black. Otherwise, it's likely normal. I would also encourage a few sips of water or hydrating fruits like the previous commentor.
Banana poo is usually little black strings in the poo.
No never seen this.. but the little balls would suggest she is constipated. Are you offering sips of water from a free flow cup? Try offering watermelon and cucumber both very water based .. why haven’t you given fruits?