Is it cruel to dress a chihuahua in a jumper and shoes, if they like it?
A jumper will keep them warm in cold weather and a light “shirt” may protect them from the sun and/or biting insects but keep in mind dogs can’t sweat to dissipate heat so let your chihuahua go au naturel if it’s hot out. I’d skip the boots unless you’re walking in snow & ice. I also think it likely your dog likes the attention you lavish upon them when you dress them up like a doll, not specifically the clothing so if it isn’t impairing the dog’s movement or causing health issues and it makes YOU happy then go for it.