v:\> echo ab%@char ab v:\> echo ab%@charcd acd
v:\> <default box character here> TCC: Unknown command "→"
Just experimenting, I found a few things that make me curious.
With ECHO and TYPE, BS is handled differently when it's at the end of a string from when it's not at the end.
Can't you use WriteConsoleOutputCharacter in both cases? It's a shame that using a custom input color together with a Unicode font clobbers those glyphs.