By default, suggestions lists that appear when typing invocations of UE4 macros do not include VA Snippets.
Enable suggestion of VA Snippets by adjusting Feature Behavior for UE4.
Visual Assist build 2258.5 and older
Enable suggestion of VA Snippets within UE4 macros by changing the value of AllowSnippetsInUnrealMarkup:
HKCU\Software\Whole Tomato\Visual Assist X\<IDE spec>\AllowSnippetsInUnrealMarkup = 01
Set the value to 00 to restore default behavior.