If a game has SSD as a requirement it's still typically possible to play it from a regular disk. But it will be a much worse experience with really abysmal loading times at least. Investing in a cheap external SSD might be the way to go if your patience isn't infinite.
Don't know if others have responded to this yet, and I'm not a hardware person, so i could be wrong, but latency on SSD through USB is not more performant than an internal spinning disk is my understanding.
