The 808 doesn’t have swing but it has some behaviour that causes subtle variation in the sound. For example triggering the kick drum repeatedly doesn’t make the exact same sound every time because of the way the envelope retriggers.
The most notable one is that sounds that are programmed on the same step do not actually trigger at exactly the same moment. They trigger one after another - very rapidly after each other, but not simultaneously. This can cause certain sounds to drift on and off the beat very slightly.
The TR-8 emulates both of these things and more (if you record the midi output into a DAW you can see the timing shift - though there’s a hidden setting in the TR-8 to turn that behaviour off), and I’m sure the TR-08 does the same.