Asterisk is a multi-protocol PABX, not a SIP Proxy.
SIP Proxy is not possible.
Registration server and Location server are only supported for the purposes of Asterisk acting as the location client. To get a registration server function with chan_sip use type=peer, with host=dynamic. The location server function isn’t externally exposed, and is automatically invoked when a call is initiated through the same peer entry. Equivalent features exist for chan_pjsip, but are rather differently implemented.
For redirection, use the Transfer application in your dialplan, without using Answer. Note that Transfer is rarely used, and the implementation is likely to be buggy, compared with Dial.