No, the Sony A7 IV is not compatible with the Sony Tough G 128GB CFexpress Type B.
CFexpress Type B is physically incompatible with CFexpress Type A slots. The Sony A7 IV has a Type A slot — Type B cards are larger and will not seat in the slot. This is a form-factor mismatch, not a speed issue.
What works instead
See all compatible camera for the Sony A7 IV →“This camera supports CFexpress Type A memory cards and SD memory cards”
Last verified:
Confidence: inferred