If possible, change {$USER.MACRO} to be resolved during LLD. Not dropped completely. In this case it won't affect search by item name.

Main use case was mapping of user macroses with context on template/host level to use on discovery phase. In this case {#LLD.MACRO} should be resolved first, then {$USER.MACRO}.

Example of user+lld macro combination:

{$FSDESCR:"{#FSNAME}"} 

Example of mapping:

Example of result after discovery:

Workaround with JS preprocessing is available, but not quite elegant.