Unadorned echo may or may not support a particular option, dependent on if it is a shell (which one?) built in or an external command. See the start & the bottom of GNU echo invocation; mix in korn-shell (sic) for extra fun.

Variable expansion(substitution) is also shell dependent ...

• generates error ${PATH/...}: Bad substitution in FreeBSD 6 /bin/sh (ash);
• generates error Missing } in tcsh 6.15*;
• at least works in zsh 4* & bash 3* here.