Here you have a camera from Fujifilm that is equipped with a LCD/OLED viewfinder and is equipped with a CMOS sensor. With a weight of 355 grams, it shouldn't come off as too cumbersome.
From Currys
FUJIFILM X-M5 Mirrorless Camera with FUJINON XC 15-45 mm f/3.5-5.6 OIS PZ Lens - Black, Black
SmartTeck
Fujifilm X-M5 Mirrorless Digital Camera - Black - Camera + XC 15-45mm -
This product is also available at 2 unverified stores.