Practically you can, but it will same as S7 FE pen, that means you can write with it but you won't be able to use Bluetooth features and air gesture because S7 FE does not have any built-in S Pen charger (like the one on the S7+).
The Pen that ships with S7 & S7+ is different from S Pen Pro. I would suggest you to buy S Pen Pro if you If you want Bluetooth and air gesture feature. Because with S Pen Pro it wouldn't matter which Tab you are using: the S Pen Pro can only be charged through its USB-C port.
The funny thing is that the S-Pen that ships with the Tab S7 FE can be charged on the Tab S7+. And since it looks identical and can hold a charge, we can only guess it also features Bluetooth support. But because the Galaxy Tab S7 FE has no S-Pen charger, its recognition was probably disabled by Samsung, and it wants you to buy the more expensive S-Pen Pro model if you want Air Gestures. Sounds like something Apple would do.
