Which motherboard has 8x/8x PCIe lanes for my use?

Build Help/Ready:

I am building an NAS/Plex/Transcoding machine. I need to have my HBA and my GPU inside. My HBA is the LSI 9305-24i, this card is a 8x, and requires 8x for full PCIe lane usage. I do plan on populating all 24 slots, at least ~20-22.

My GPU is an Intel ARC A380, I don't think it will need the full 16x lane, I imagine an 8x or even a 4x /should/ be okay for a GPU like this?

Almost every consumer mother board on the market I see is has 1-3 PCIe 16x slots, but they only run at 16x/4x/4x at best.

Can anyone recommend me a mobo from the Intel 12th era, Z790, that can maybe do 8x/8x/4x? Is bifurication the only way? I dont want to have to split a single slot with some adapter, would be difficult in my limited case space to even somehow set that up.

If this isn't possible, do I need to go a platform that has more PCIe lanes?

I would like the final last PCI slot to be populated by a 10G NIC as well.

I am in the US, don't really have a budget. Just looking for possible parts.