There's a charger outside the building in one of the parking spots for the hotel.
It's not super visible, but there are actually 2 different parking spots and both can be reached by the charger. The Tesla in one of my pictures isn't very well parked.
Their website explains the access modalities https://www.zeithotel.ch/en/faq
Arrival and parking
Private car: Please drive via Interlaken West even if the route planner suggests via Gunten - Sigriswil. Thus, the approach is usually possible without snow chains even in winter. The road between Sigriswil and Beatenberg is often closed. Otherwise we will be happy to inform you in advance if the road is open. You will find the hotel shortly after the Hotel Dorint on the left side. The parking spaces are distributed around the hotel and are available free of charge. Three of the parking spaces are located across the street above the small driveway.
We also have an electric charging station for your car. Please reserve these in advance. The cost is CHF 20 per charge.
Not sure what the power of the charging station is. I didn't stay at the hotel and didn't charge.
This location is not on Chargemap.