Yes, it's fine with 8 GB plus 8 GB plus 16 GB of RAM.
Yes, it's fine with 8 GB plus 8 GB plus 16 GB of RAM.
Use an Intel setup with 2x8 in one lane and 1x16 in another, then verify dual-channel status via CPU-Z or hwinfo.
No, I don't need more than 16GB. Would you like an additional 8x2 and four 8GB units?
It doesn't matter if you're using a single-channel setup on either platform. What AMD CPU model are you running? Different models handle multiple sticks differently.
Which board are you using? According to Asus in their B550 manuals, it's still possible, though I haven't found any official documentation for AMD. Do you have enough memory to test it? If so, I'd just give it a go and check the results.
The 5600 operates smoothly in 4x4 mode, and using 8GB drives should work fine.