A.2.4 Does PuTTY support local echo?

Yes. Version 0.52 has proper support for local echo.

In version 0.51 and before, local echo could not be separated from local line editing (where you type a line of text locally, and it is not sent to the server until you press Return, so you have the chance to edit it and correct mistakes before the server sees it). New in version 0.52, local echo and local line editing are separate options, and by default PuTTY will try to determine automatically whether to enable them or not, based on which protocol you have selected and also based on hints from the server. If you have a problem with PuTTY's default choice, you can force each option to be enabled or disabled as you choose. The controls are in the Terminal panel, in the section marked ‘Line discipline options’.