@Minnie Thanks for reaching out!
If you are asking about the Leki Fitness Walking Tips, with their sloping rubber pad on the bottom, then you are correct that they are designed for use with Leki Nordic Walking poles. Based on what we can tell from some of the reviews of the fitness walking tips, they will fit on your trekking poles but there is some movement in the tips when you put pressure on them. If you'd like to look at a pair of Leki Nordic Walking poles you can check out the Leki Traveller Carbon Poles.
Hopefully this helps!