Sometimes. Note that both your ingredients are liquids, however.

I use buttermilk powder for quite a few recipes so that I can control the liquid content independently of the acid and fat content.

I feel your pain - dealt with a lot of those calculations so the calculator could avoid powders!

For sure - if you check "milk" and "lemon" and select maximum tang, you'll get nice tangy pancakes. I opted away from vinegar due to taste but would be curious to hear if someone tests vinegar vs lemon!

This works with dairy-free milk too. My daughter has a dairy allergy and figuring out we could turn pea milk into pea buttermilk with a tbsp of white vinegar upped her pancake experience significantly.