Yes, the Sony A7C II is compatible with the Sony SF-M Tough Series 128GB SD UHS-II.
Sony A7C II Slot 1 accepts full-size SD cards directly. Sony SF-M Tough Series 128GB SD UHS-II is V60 class. Meets the floor for: 4K30 (30 MB/s floor); 4K60 (60 MB/s floor). (Peak write 150 MB/s is not evidence of sustained performance; the V60 class rating above decides this.)
Limitation
Cannot record XAVC S-I 4K -- requires Video Speed Class V90, this card is V60. Works for standard XAVC HS/S 4K and S&Q Motion 4K (V60 sufficient).
“Sony A7C II Help Guide: XAVC HS 4K at 200Mbps requires SDHC/SDXC U3 or higher; XAVC S-I 4K at 600Mbps requires SDXC V90 — V60 card supports standard 4K formats but not intra-frame 4K.”
“For S&Q Motion shooting (When [ Proxy Recording] is set to [Off] ) File formats and compatible memory cards are as follows. File Format Maximum recordable bit rate when recording Supported memory card XAVC HS 4K 250Mbps SDXC V60 or higher”
Last verified:
Compatibility inferred from spec rule (citations above are manufacturer-verified)