Yes, the Panasonic LUMIX GH7 is compatible with the SanDisk Extreme PRO SD UHS-II V90 128GB.
Panasonic LUMIX GH7's SD slot (Slot 2) accepts SanDisk Extreme PRO SD UHS-II V90 128GB directly. SanDisk Extreme PRO SD UHS-II V90 128GB is V90 class. Clears: Motion pictures (72 Mbps, requires V10); Motion pictures (200 Mbps, requires U3); Motion pictures (400 Mbps, requires V60); Motion pictures (600 Mbps, requires V90). Above 600Mbps -- including variable frame rate with ALL-Intra and internal ProRes/ProRes RAW recording -- Panasonic's own spec states these require a CFexpress card; no SD card of any class can record them.
Limitation
Cannot record above 600Mbps on the SD slot (variable frame rate ALL-Intra, ProRes/ProRes RAW) -- CFexpress card only, no SD card of any class can do this. Works for every SD-eligible Long-GOP mode up to 600Mbps (Video Speed Class 90).
“Motion pictures with 72Mbps or less: CFexpress card, SD memory card with SD Speed Class with Class 10 or Video Speed Class 10 or higher Motion pictures with 200Mbps or less: CFexpress card, SD memory card with UHS-I / UHS-II UHS Speed Class 3 (U3) or Video Speed Class 30 or higher Motion pictures with 400Mbps or less: CFexpress card, SD memory card with Video Speed Class 60 or higher Motion pictures with 600Mbps or less: CFexpress card, SD memory card with Video Speed Class 90 Motion pictures with 800Mbps or more, variable frame rate with ALL-Intra, or ProRes: CFexpress card”
Last verified:
Compatibility inferred from spec rule (citations above are manufacturer-verified)