Here are all the GNOME Core Apps I could find on Flathub.
- Audio Player
flatpak install flathub org.gnome.Decibels
- Calculator
flatpak install flathub org.gnome.Calculator
- Calendar
flatpak install flathub org.gnome.Calendar
- Camera
flatpak install flathub org.gnome.Snapshot
- Characters
flatpak install flathub org.gnome.Characters
- Clocks
flatpak install flathub org.gnome.clocks
- Connections
flatpak install flathub org.gnome.Connections
- Contacts
flatpak install flathub org.gnome.Contacts
- Disk Usage Analyzer
flatpak install flathub org.gnome.baobab
- Document Scanner
flatpak install flathub org.gnome.SimpleScan
- Document Viewer
flatpak install flathub org.gnome.Evince
- Extensions
flatpak install flathub org.gnome.Extensions
- Fonts
flatpak install flathub org.gnome.font-viewer
- Image Viewer
flatpak install flathub org.gnome.Loupe
- Logs
flatpak install flathub org.gnome.Logs
- Maps
flatpak install flathub org.gnome.Maps
- Music
flatpak install flathub org.gnome.Music
- Text Editor
flatpak install flathub org.gnome.TextEditor
- Videos
flatpak install flathub org.gnome.Totem
- Weather
flatpak install flathub org.gnome.Weather
- Web
flatpak install flathub org.gnome.Epiphany
Command to uninstall native apps from Arch Linux
$ sudo pacman -Rs decibels gnome-calculator gnome-calendar snapshot gnome-characters gnome-clocks gnome-connections gnome-contacts baobab simple-scan gnome-shell-extensions gnome-font-viewer loupe gnome-maps gnome-music gnome-text-editor totem gnome-weather epiphany