Samsung is not a fond of installing third party firmwares on the S9 FE but you can do that by installing a custom recovery like TWRP to make that happen.
We now have access to TWRP, a custom recovery for the Samsung Galaxy S9 FE Plus WiFi (SM-X610), Galaxy Tab S9 FE Wifi (SM-X510) and Galaxy Tab S9 FE 5G. Before you proceed, you must unlock the bootloader, which you can do so by following these steps.
Open the Settings app, enter Developer Options and enable OEM unlocking. If you don’t see Developer Options, enter into About phone>Software info and tap “Build number” 10 times to show it on your Galaxy Tab S9 FE.
Enter Download Mode: to do so power off your Galaxy Tab S9 FE, connect it to a computer via an USB cable and hold both volume up and volume down buttons.
Long press volume up to unlock the bootloader. This will wipe your data and your phone will automatically reboot.
Go through the initial setup. Skip through all the steps since data will be wiped again later. Make sure to connect the device to Internet during the setup.
Enter Developer Options and check that the OEM unlocking option exists and is grayed out. This means our bootloader is unlocked and your phone has no KnoxGuard lock set.
Now, let us flash the TWRP. Before that, download the file for your tablet.
- SM-X516B: GitHub Releases (direct link)
- Galaxy Tab S9 FE Wifi (SM-X510)
- Galaxy Tab S9 FE Plus Wifi (SM-X610)
Connect your Galaxy Tab S9 FE to your PC and boot in Download Mode – power off your device and hold both volume up and volume down buttons.
Open Odin3 on your windows computer, select the TWRP tar by clicking the “AP” button, then press the Start button.
Reboot Galaxy Tab S9 FE in recovery mode: while it still plugged in your PC, hold both the power and volume up buttons.
Once TWRP has booted you need to format again your data partition in order to be able to boot in system again. To do so touch Wipe>Format Data and follow the instructions in screen.