No, I have no idea... I wish!!! I try to know from previous test-takers about what kind of speaking tests and writing subjects. For example for my writing test, last time was " The adds effect our buying behavior" this was for Section B, but for Section A there are endless probabilities. Generally, in my training, I search for different subjects from IELTS and anything about TEF online, and write as much as I could. The practice helps to think faster, have more vocabulary and more ideas about different subjects. At a certain point, things intercross in writing. Other than this, emerge yourself in French, watch movies in French audio and subtitle, which will help you significantly with listening.
If you are planning to take eTEF so you have to get used to using ALT codes to write the accents because I have been told that listening, reading and writing will be done on the computer. If you are planning to take the paper TEF, so get used to writing, because your hand memory will help with memorizing the spelling and the accents too... so write A LOT. Keep in mind that, reading will help with writing and listening will help with speaking.
I am using many sources to learn on my own. The full list is listed above (after October 2019). But the most useful for the test were
Prepmyfuture
Lawless french which covered a lot.
News in Slow french as well it helps a lot.
Let me know if I can help with anything.
Good Luck to all!