Yes, the Sony A7 IV is compatible with the Transcend 700S V90 128GB.
Transcend 700S is Video Speed Class V90 (180 MB/s rated write). Sony A7 IV's SD slot requires Video Speed Class V90 or higher for its top XAVC S-I 4K (600Mbps) mode per Sony's own Help Guide -- this card meets that class requirement.
“Sony A7 IV Help Guide: XAVC S-I 4K at 600Mbps requires SDXC V90 or higher; XAVC HS 4K at 200Mbps requires SDHC/SDXC U3/V30 or higher — V90 SD card meets all SD-slot recording requirements.”
Last verified:
Compatibility inferred from spec rule (citations above are manufacturer-verified)