Well, it is possible to assign hotkeys or chords to the first 50 templates in global templates list in the key mappings configuration dialog. This is a feature from UltraEdit prior v18.00 which supported only up to 50 templates in a single template file.
But since UE v18.00 and the smart templates feature there is most often no real need anymore for assigning hotkeys to templates. With the auto-suggest templates feature as demonstrated on
Smart Templates and configured at
Advanced - Configuration - Templates just the name of a template must be typed and a short pause must be made to get the suitable template suggested with a name equal the already entered word.
Alternatively the auto-complete feature can be used which shows at top of the list those templates of which name starts with the same characters as the already typed word. If auto-complete feature is not enabled, typing let's say the first 3 characters of a template name, hitting Ctrl+Space to open the auto-complete list, selecting the template to insert with the up/down arrow keys and hitting key RETURN results also in inserting the template by using keyboard only.
On topic
smart templates management rhapdog and I discussed best practices on naming the templates which make it easy to insert them via auto-suggest smart templates or auto-complete feature.
So hotkeys make sense nowadays only for smart templates which are designed to work on a selected text where auto-suggest and auto-complete feature for inserting a template cannot be used.
If the first 50 templates in global template list are not enough, some of the HTML toolbar commands can be used too. The HTML toolbar commands can be customized, support inserting strings around a selected text and for some of them hotkeys can be assigned too. Of course the HTML toolbar commands cannot be used only for HTML, they can be used for every language despite their name.