I created three AVDs base on Android Q (API 29), using these system images:
Android 10(Google Play), Android 10(Google APIs), Android 10.
All of these emulators
I had similar issues that were not fixed with the installation hints above.
I finally solved the problem following this instructions to Configure VM acceleration on Linux: https://help.ubuntu.com/community/KVM/Installation
My problem turned out to be wrong user-groups configuration. The following commands finally made it work for me:
$ sudo adduser libvirtd
$ sudo chown root:libvirtd /dev/kvm