Yes, the Fujifilm X-S20 is compatible with the Transcend 700S V90 128GB.
Transcend 700S V90 is V90 class. Meets the floor for: 4K30 (30 MB/s floor); 4K60 (60 MB/s floor). (Rated write 180 MB/s is not evidence of sustained performance; the V90 class rating above decides this.)
“*For recording movies in 360Mbps, use a SD memory card with Video Speed Class 60 or higher.”
Last verified:
Compatibility inferred from spec rule (citations above are manufacturer-verified)