video doorbell

In my new home there is a Deta c3504 chime installed. I am thinking about adding Google Nest video doorbell but I found that it needs 8V minimum to operate. Unfortunately Deta gives 6V and drops below that if the button is pushed. I found this on Reddit...

Hi just got the battery 2k Eufy and was hoping to wire it up using our existing doorbell wires,only problem is the transformer isn’t powerful enough its only 8V. IMG_20210209_155939.jpg706×941 22.1 KB IMG_20210209_155950.jpg650×867 54.3 KB Am i right in thinking i have 2 options...