Add an external plugin to a Cubase noise gate

Hi,
since Cubase noise gates have a maximum attack time of 1 sec and I need 2,5 sec instead, I need to add an external plugin (FabFilter Timeless 3) to the Cubase default noise gate.
Basically one track has to start 2,5 sec after the other, but they still HAVE TO FINISH AT THE SAME TIME. How do I integrate the plugin into the noise gate? Or do they have to be two different inserts?

Alternatively, does anyone have a tipp about how to solve this problem in a different way or with a different plugin?
Thanks in advance!
Marta

Using automation?

No, I set all parameters manually

No, I mean using automation gives you the possibility to determine when and how a track starts.

You could just cut the Audio wherever you like and reduce the gain on the first clip.