Try EchoTap for FREE first (limited to only the tap tempo feature).
Echo Control is a Max for Live plugin that allows you to control Echo's time knob by tapping out a tempo separate from the global Ableton tempo. In addition to tapping out a tempo, it is designed to maximize your hardware controls to modulate dry/wet mix, input mute, feedback, feedback slam, signal clearing, single-knob LP/HP, repitch, and more with only 8 hardware CCs, or just four knobs on a Midifighter twister.
Effectively, Echo Control measures the time of your tapping (after three taps) and then finds the nearest value in a table of 127 values that correspond to a macro controlling Echo's time knob. It's not a perfect match, but you can expect it to be accurate within about 20ms.
If you want to have the experience of manipulating an analog delay while still working in Ableton, then this is for you!
Requires Ableton Live Suite 11 to function. You'll receive an Ableton project file with Echo Control loaded as an instrument rack. Simply save the rack to your User Library and you're good to go!