No, the ProGrade Digital CFexpress Type B Gold 128GB is not compatible with the Sony A7 IV.
CFexpress Type B card cannot physically seat in the Sony A7 IV's Type A slot. Form-factor mismatch — not a write-speed issue. The A7 IV's two slots take CFexpress Type A or SD UHS-II cards only -- use a Type A or SD card instead.
What works instead
See all compatible memory card for the ProGrade Digital CFexpress Type B Gold 128GB →“This camera supports CFexpress Type A memory cards and SD memory cards”
Last verified:
Confidence: inferred