#️is it possible to edit multiple services at once?

No it is not possible but you can do the following on the settings tab of Cowlendar

You can block timeslots across all services at once

You can block dates across all services at once

You can setup a maximum booking per timeslot across all services at once

But you can not handle all the availabilities at once in the settings tab. This has to be done per service in "my services" tab.