Kdenlive Render Effects
Yes, you can preview effects using timeline preview rendering since version 16.08 (video tutorial):


Set in and out points using I and O keys for the area in which your effect is active.
In the main menu in Timeline/Timeline Preview press Add preview zone.
In the same menu, press Start Preview Render and wait until the red bar turns green at the top of the timeline.


Any change to the area - including moving clips or adding effects to clips in it - will result in requiring to re-render to regain the playback speed enhancement.

In case 16.08 or later is not available on Linux Mint yet, you might be able to install it manually (video guide):

sudo add-apt-repository ppa:kdenlive/kdenlive-stable
sudo apt-get update
sudo apt-get install kdenlive