
Samsung Galaxy Tab S9 FE, 6GB RAM +
Every official firmware build for SM-X510N, newest first: one row per build with all regions (CSC) that received it.
Box codes of SM-X510N for different colors and markets. Firmware is chosen by the model code SM-X510N and your region (CSC), not by the SKU.

SM-X510

SM-X516N

SM-X610N

SM-X520N

SM-X528U
You can find the firmware on the model: SM-X510N page.
Yes, all firmware files for SM-X510N are 100% official, original, and obtained directly from Samsung servers.
To flash SM-X510N, you need to download the appropriate firmware, put your device into Download Mode, and use the Odin tool to load the BL, AP, CP, and CSC files.
Downgrading is only possible if the bootloader version (binary bit) of the old firmware matches the current one. Always check the binary version before flashing SM-X510N.