I moved to a new address (same county) on Jan 1st 2019, and I filed my 2018 taxes under the new address. Do I still need to fill 8822 after I file this year for 2019?

No.  If you used your current address for your 2018 return (due last April) and you use your current address now for 2019, you don't need to also send a separate change of address form.