UPDATE:

I tried the new packages, and it installed all except one package (librsvg2-common), breaking my system.

DO AT YOUR OWN RISK!

UPDATE 2:

Anyone else facing issue with the aforementioned package, following command allowed me to get my stable system back and install rest of 6-v3 packages.

sudo mv /usr/share/doc/librsvg2-common/changelog.Debian.gz /usr/share/doc/librsvg2-common/changelog.Debian.gz_BK