Scalable Link Interface - Wikipedia
But maybe EVGA will come out latter with a 0-Slot (2-Slot) NVLink SLI Bridge as the did for the Older HB SLI Bridges. Note that Jeff said "Currently" But then is it really practical to run Two RTX Cards on a mATX Motherboard.
GeForce RTX 2080 Ti Graphics Card
GeForce RTX NVLink Bridge 4-Slot version for when there are two empty slots between the cards. Connects two NVLink SLI-ready 3090 Series graphics cards.
EVGA PRO SLI Bridge HB - 4-Slot Spacing New Open Box
Buy ASUS Republic of Gamers GeForce RTX NVLink SLI Bridge (4-Slot Spacing) featuring For Select NVIDIA RTX Graphics Cards, ASUS AURA SYNC RGB Support.