There are two versions of the ASUS TUF GAMING Z790-PLUS WiFi. A DDR5 version (https://www.digitec.ch/fr/s1/product/asus-mb-asus-tuf-gaming-z790-plus-wifi-intel1700ddr5atx-lga-1700-intel-z790-atx-carte-mere-23486566) and a DDR4 version which is this one (it has the D4 in addition in the name of the card).

So this D4 card is DDR4 only.