I found this useful. https://www.ketofitnessclub.com/blogs/starter-information/sweeteners
First I tried Pure via and that was OK, now I'm on Truvia and don't find it tastes so sweet. I hear of others who like monkfruit.
It's really a matter of trying and personal choice. I just know I'm using less and less as it all tastes 'wrong' now
I use either erythritol or truvia. I find truvia is a little sweeter than ordinary sugar, erythritol on it s own not quite as sweet so good for baking.
Stevia is always cut with something else in granulated/powder form as it is extremely sweet on its own. Check what it is cut with as some of the cheaper brands cut it with sweeteners that can affect your blood sugar or have laxative effects.