I have some kidney beans that I soaked overnight to cook the next day but didn't get a chance and accidentally left them out and it's been fairly hot lately. Some of the beans started to get little sprouts poking out. There's also a little bit of a smell. Is it still safe to cook the batch or have I wasted a bunch of beans?
This is totally safe to eat as long as you cook them. The taste and the texture would be a little bit different than what you use to though.
Here is an article about the safety of eating sprouted beans.
Whether they're okay to eat depends on whether they've started to spoil. You said there's a bit of a smell. Sprouting beans shouldn't have a bad smell. If any feel at all slimy or mushy (not just softer like soaked beans are), I'd err on the side of caution and discard them. You posted your question on June 17 and it's now June 21 so you've likely already used or tossed them. But in future for you or anyone else who reads this, sprouted beans are safe unless they've started rotting, even a little.
Personally, I would not cook & serve those beans. Beans have such an "acid-y" (not a word, I know) kind of taste anyways, which can & does show up in the final result despite the salt and spices you add...
Then there's the gas issue from those little buggers! Suppose the chemical changes in the bean which resulted in baby sprouts also results in more digestibility issues?
Dried beans cooked into soups & stews are the most under appreciated protein in the world. Seriously. I would not risk turning any of your family or friends into bean-haters; Especially since they are the last affordable but high-quality food.