I had the same issue before on my 2017 iA. It happened after I got the engine oil replaced with the 5W-30 engine oil at a Toyota dealer. The vibration issue disappeared after I replaced it again with the Costco Kirkland 0W-20 engine oil. I guess the vibration issue was due to the higher viscosity of the 5W-30 oil used by the Toyota dealer (the owner's manual recommends 0W-20).