Doesn't matter. Type 4 are reverse compatible. So, while the A7 IV can't use the added performance of the Type 4, it can still use the card limited to Type 2 performance.

A7 IV doesn't support Type A 4.0.

AI sez: The CHIPFANCIER CFexpress Type A 4.0 memory card offers 1700MB/s read speeds and is VPG400 certified, making it suitable for 8K video and high-speed shooting. However, some users have reported limitations in frame rates with this card.  Don't know if that applies, but it sounds similar. Any chance on using/getting a different card? The A7 IV has a ridiculous buffer, it shouldn't slow down at all with a good card.