Based on information I have researched, the Active variant of the 75t have a better IP (ingress protection, i.e. waterproof protection) rating. They also come in a soft touch plastic (slightly rubbery) finish, rather than the smooth plastic finish that the Elite 75ts have.
The Actives will have some additional software features released in Q2 of 2020, but it is believed that the Elites will receive the same features via a firmware update, though Jabra has not confirmed that yet.
I personally use my Jabras almost exclusively for exercise and running, so I opted for the Elite Active 75t to replace my current Elite Active 65t as I value the waterproofing as well as the rubbery texture, which I have found helps keep them in my ears a little bit better. That said, my wife has the Elite 75ts, and they are extremely secure in her ears and mine.