Virtual queues are booked using the Disneyland Paris app and allow you to book a meet with a character and then have timer until it is your turn to go to the meet location. This means you can do other things in the meantime and that you do not need to stand in a long physical queue. 

The process for these meets is the same for everyone, there is no difference if you have a priority pass or an easy access pass or have any disability, as the virtual queue minimises physical queuing and the locations all have step free access. 

To book a slot you need to have your tickets or annual pass linked in the app and be signed in, you also ned to have used those tickets or passes to enter either of the parks that day, until you have passed through either parks turnstiles you can't book a slot. 

Slots usually open up at 9.45am and 2pm and occasionally an extra one around 5pm for some characters like the hero training centre, but it will state in the app the next time booking opens.

You can find it in the app by looking at the map, switching to list, scroll across to characters and select the character you want. If the queue has spaces it will let you select the meet, who in your group wants to visit, then confirm your booking and give you an estimated wait time in minutes. You are then free to do other things until your time. The app will notify you (if your permissions allow that) when your time is close and again when it's your turn, but if you want to check in the meantime you can see your wait time in the account section of the app, under my tickets and passes.

You can technically book up to 5 virtual queues per day, however you can only hold one booking at a time and as they are usually only released twice a day in reality you are unlikely to ever get more than 2 in a day.

The virtual queues fill up very very fast, usually within a minute or two so you need to decide which character you are wanting to try for and be ready in the app a minute or two before bookings open.