According to your link (and all other articles I found on that vessel), that ferry is capable of operating all-electric, but actually operating as a hybrid.
The Seattle ferries GP was talking are also retrofitted to be hybrid-electric, so that does seem very comparable
Although the news at that time was about delivery of a first electric ferry, that was 2021 and things change. The Ferry company's web site says now it has three electric ferries as a result of conversions and indeed they charge at both ends of the route. It's in Norwegian but the translation looks reasonable to me.