Yes, the Fujifilm X-T5 is compatible with the Samsung PRO Plus 256GB SD.
Samsung PRO Plus is UHS-I, Video Speed Class V30 (which includes UHS Speed Class 3). Per the X-T5 manual, 100/200 Mbps movie modes only require UHS Speed Class 3 or better -- this card clears that. The X-T5's highest 4K 60p mode (360 Mbps) requires Video Speed Class V60 or better, which this card does not meet.
Limitation
Works for 100/200 Mbps movie modes only -- cannot sustain the X-T5's highest 360 Mbps 4K 60p mode (requires V60, this card is V30).
“Movies with a bit rate of 360 Mbps can be recorded to cards with a Video Speed Class of V60 or better. Movies with a bit rate of 100 or 200 Mbps can be recorded to cards with a UHS Speed Class of 3 or better.”
Last verified:
Compatibility inferred from spec rule (citations above are manufacturer-verified)