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.
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.
I was initially responding to a post stating that there were many all-electric ferries, and my point was that there were none (operational) of a size comparable to WA state ferries. https://news.ycombinator.com/item?id=42197763
There are many large hybrid vessels; notably, this has been common for submarines for a very long time. The largest currently operational diesel-electric (hybrid) submarine seems to be the Chinese Qing-class, of ~3800 tons surfaced displacement.
Here is the largest e-ferry: https://en.wikipedia.org/wiki/E-ferry_Ellen
And a guide to the WA fleet: https://wsdot.wa.gov/sites/default/files/2021-10/WSF-FleetGu...