What’s the shortcut to switch between app documents in a Spanish keyboard

⌘+⌥+←/↑/→/↓ will let you navigate split panes in the direction of the arrow, i.e. when using ⌘+D to split panes vertically, ⌘+⌥+← and ⌘+⌥+→ will let you switch between the panes.

Note: ⌥ is the [alt] key

You could make your custom keyboard shortcuts.

Adding a Custom Keyboard Shortcut Command Set

Personalize your Xcode experience by adding your own set of keyboard shortcuts. Xcode provides a default set of shortcuts for most menu commands and common text editing commands. Many of these default shortcuts are based on the commonly used Emacs key bindings.

In the Key Bindings preferences pane, choose Manage Key Bindings from the Key Bindings set pop-up menu.

Click the Add button in the lower left of the dialog.

Choose Duplicate or a template option from the pop-up menu.
Name your new command set file.

You can override the default shortcuts by creating a new command set with your preferred shortcuts. This new set is stored in the folder ~/Library/Developer/Xcode/UserData/KeyBindings/ as a property list with the extension .idekeybindings.

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