Issues with mood when stimulatns wear off is common. It’s called rebound. Some doctors will prescribe a small sort-acting dose for the afternoon to ease the transition.
But, if that doesn’t work, there are many, many ADHD stimulants to try. There are two types of stimulants: amphetamine (Adderall, Vyvanse, Evekeo…) and methylphenidate (Ritalin, Concerta, Quillivant…). Almost everyone does well on one type or the other, but not both. She could do better with amphetamine-based stimulants, but there’s no way to know which type is best for her without trying both.
ADDitude Community Moderator, Parenting ADHD Coach, Podcaster & Author, Mom to teen w/ ADHD, LDs, and autism