Some comments from @sipa in #12702.

___

Yes, I think `importmulti` is superior in every way, except:
* Slightly less convenient to use (it requires redundant information, as you have to explicitly state what you want to import, and then give the keys/... to enable that).
* ~Doesn't support P2SH-P2WPKH yet~. Added in #14454

The latter can be fixed by just adding support for that case. The former can be improved by adding 'default' cases (e.g. if you prove a WIF private key, it can permit omitting the address, ...).

std::string label = LabelFromValue(request.params[0]);
    
    UniValue ret(UniValue::VOBJ);
    for (const std::pair<const CTxDestination, CAddressBookData>& item : pwallet->mapAddressBook) {
        if (item.second.name == label) {
            ret.pushKV(EncodeDestination(item.first), AddressBookDataToJSON(item.second, false));
        }
    }
    if (ret.empty()) {
        throw JSONRPCError(RPC_WALLET_INVALID_LABEL_NAME, std::string("No addresses with label " + label));
    }
    return ret;
}
static UniValue listlabels(const JSONRPCRequest& request)
{
    std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
    CWallet* const pwallet = wallet.get();
    if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
        return NullUniValue;
    }
    if (request.fHelp || request.params.size() > 1)
        throw std::runtime_error(
            "listlabels ( \"purpose\" )\n"
            "\nReturns the list of all labels, or labels that are assigned to addresses with a specific purpose.\n"
            "\nArguments:\n"
            "1. \"purpose\"    (string, optional) Address purpose to list labels for ('send','receive'). An empty string is the same as not providing this argument.\n"
            "\nResult:\n"
            "[               (json array of string)\n"
            "  \"label\",      (string) Label name\n"
            "  ...\n"