This cookbook is metric: https://www.amazon.ca/Modern-Vegetarian-Adventures-Contemporary-Palate/dp/1906868808
However I really don't think the imperial is the problem. You're probably converting wrong if you're consistently off enough that it's inedible. I've never had trouble with any recipe.
The conversion isn't hard. A tsp is 5ml, a tbsp is 15ml, an ounce is 30ml, and a cup is 240ml.
A stick of butter is 1/2 a cup. It's very odd because my butter never comes in sticks, but it's a thing to sell 2 cups of butter split into four 1/2 cup sticks in the package. What my butter does have is a measurement on the inside of the package with a line at 1/4 cup, 1/2 cup, and 1 cup so you know where to cut.