From what I can gather, Etudes written specifically for speed and Toccatas have a lot of similarities. They are both fast with lightly fingered passages and they both emphasize dexterity. The main difference I see is time period. Etudes are more common from the Classical era onwards and Toccatas are more common in the Baroque. And instrumentation, while lots of Etudes are written for piano, there's also Etudes for Flute, Violin, etc. Toccatas are mainly for keyboard instruments, although some are for plucked string instruments.
Toccatas often have canon or fugue like passages in them, but that could just be an artifact of them being from the Baroque, it's not like Etudes can't have fugal imitation in them. But canons and especially fugues are more common in the Baroque, so it makes sense that fugal imitation and canonic passages would be very common in Toccatas. Toccatas also from what I gather, tend to use almost the entire range of the instrument in question, from the high register all the way down to the lowest bass notes. But there are plenty of Etudes with a wide range in for example Chopin, so range isn't really a strong enough difference unless you're talking just the Etudes composed by the likes of Czerny in the Classical Era.
And like I said before, speed and emphasis on dexterity are things that both Etudes and Toccatas have. And for those saying that Etudes can be slow, well Toccatas often have slow sections to them, especially organ Toccatas.
So, are there any differences between Etudes and Toccatas besides time period and instrumentation?