First of all, we will see the different possibilities offered by Recalbox to change the disc.
Put all disks in one .PBP file. You can change the disk in the Retroarch menu.
.SBI files cannot be used in multi-disk games..PBP format.The following disk is searched in the Retroarch menu by the file system.
.BIN / .CUE format.Therefore, games with LibCrypt and multi-disk protection are a real pain in these two modes.
Just create a .M3U file for each multi-disk game. This file will contain the names some files. For example:

The last aspect should be as follows:

As you can see in this example, there are .CUE / .BIN / .SBI per disk and one .M3U per multi-disk game.
.SBI files can be used.There is only advantages.
Some games have multiple tracks per disk. This means that the .CUE file requires multiple entries (one per track).
Example of a multi-track .CUE:

The last aspect should be the following:

.BIN extension: special caseRom files with the .BIN extension are also supported but require a .CUE file to be started.
.CUE extension: how does it work?A .CUE file is, quite simply, a text file whose extension has been changed from .TXT to .CUE . It must have the same name as the .BIN file it accompanies and it contains the information necessary to launch the .BIN file. This is also working if you have multiple .BIN files with only one .CUE (this is depending of the games).
.M3U extension: manage multi-CD gamesMultiple CDs of the same game can be loaded simultaneously into RetroArch by creating a .M3U playlist file (plain text .TXT with a .M3U extension).
A .m3u playlist can be used with any extension which have a game into multiple supports, it can be cartridge or CD.
You need to create a new file named <game_name>.m3u.
You have 2 examples below with
.BIN/.CUEand.CHDextensions.
.CUE filesWe create the file Final Fantasy (France).m3u with the following content:
Final Fantasy VII (France) (Disc 1).cue
Final Fantasy VII (France) (Disc 2).cue
Final Fantasy VII (France) (Disc 3).cue
.CHD filesWe create the file Final Fantasy (France).m3u with the following content:
Final Fantasy VII (France) (Disc 1).chd
Final Fantasy VII (France) (Disc 2).chd
Final Fantasy VII (France) (Disc 3).chd
If you need to change the disk while the game is running, you should do the following:
HK key + Left Joystick (Up direction)HK key + Left Joystick (Right or Left direction)HK key + Left Joystick (Up)This works if you have your milti-disc set in a .M3U file.
.ECM and .APE files?You have to unzip them. See this guide to do so.
Hotkey + B.Controls > Port 1 Controls.
analog in the Device Type option (same for all the pads you want).
.CUE file, how do I do it?If you only have a .BIN file and no .CUE file, you can generate it in several ways:
You can also get it from Redump by going to the corresponding game page.