There’s not a whole lot to say about RAM.
Intel platforms will pretty much take whatever you slot in, and the amount you can pass to your VM is the only relevant metric to passthrough gaming.
AMD platforms will need to be vetted according to your motherboard’s compatibility list, and Samsung B-Die kits will generally perform better. Ryzen does scale a bit more dramatically with increased frequency due to the way it’s memory subsystem and CCX interconnects work, but as long as it’s listed as compatible you shouldn’t run into any issues. Generally, you want to buy the cheapest sticks you can find from a reputable brand.
[***] B-Die isn’t magic, it just tends to be more compatible with AMD platforms.