Visited on August 24.
There are no parking spaces outside, the chargers must be in the underground parking.
There's an EV sign next to the ramp, but no other instructions. Unclear if this mean you can ring them to get access to the chargers.
I didn't try to drive a car down the ramp to see if the door would open automatically. Since there's an interphone/badge scanner I assume you can't just enter without interaction.
The website makes no mention of the parking options. They have a bar/restaurant, presumably primarily for their residents and their visitors https://eira.swiss/