How to send bitcoin offline or on localhost using bitcoinj liberary

Question

I am developing a POC application where I will have multiple bitcoin wallets of different users. I am looking for any way to send bitcoin from one wallet to another wallet on localhost itself, without using network to avoid network fees. For better understanding; look the case as if I have 2 or more bitcoin wallet files with me on my local system which contains all the details of the wallet to access it. Is there any way to transfer bitcoins from one wallet to another offline (without using online network). I tried to create 2 wallet wallet using

WalletAppKit kit = new WalletAppKit(params, new File("./wallet"), filePrefix);
kit.startAsync();
kit.awaitRunning();

this created wallet when I used to different filePrefix or I can create it by

Wallet wallet = new Wallet(params);
wallet.autoSaveFile(true);

Now I have 2 wallets on my machine. I tried to create PeerGroup and tried to connectToLocalhost() but every time its shows (below is the part of log)

16:34:55.301 [bitcoinj user thread] DEBUG org.bitcoinj.core.BitcoinSerializer - Sending tx message: 0b110907747800000000000000000000e1000000cf9e6d5001000000010816112030be2164acba755cea8f9ea76acd405e3414518efbf04ce498955583000000006a473044022042177736c663fdc7dafe155999c4b4a6cdb63f1c6213c2a24a690da9f77a35c00220506f7238c534983c8d3d279cda4e9578c6036730f3ac043b68467fcf28597e1c0121037f86b44d10a225a21f6c3eddf918e4817ac240b7c3748c0cf631b9629bbc1fecffffffff02a0860100000000001976a914ea382d5c3e75cb3d73248e9eec0ab166782af95e88acc0280d00000000001976a914cb089faa36b2230bf0ec2e5d7052e529db6ce0be88ac00000000
16:34:55.303 [bitcoinj user thread] DEBUG org.bitcoinj.wallet.Wallet - Received tx we already saw in a block or created ourselves: 5df3592f352825b51cf3891e54e739bc6ce2f335570cf285b9fde594506d9ecf
16:34:55.303 [BlockingClient network thread for seed.testnet.bitcoin.sprovoost.nl/190.85.201.38:18333] INFO org.bitcoinj.core.Peer - Announcing to seed.testnet.bitcoin.sprovoost.nl/190.85.201.38:18333 as: /bitcoinj:0.15.6/earnography-server:1.0/
Peer connected
16:34:55.303 [BlockingClient network thread for seed.testnet.bitcoin.sprovoost.nl/190.85.201.38:18333] DEBUG org.bitcoinj.core.BitcoinSerializer - Sending version message: 0b11090776657273696f6e00000000007e000000effbf8657c1101000000000000000000d67c0c5e00000000000000000000000000000000000000000000ffffbe55c926479d000000000000000000000000000000000000ffff7f000001479d0000000000000000282f626974636f696e6a3a302e31352e362f6561726e6f6772617068792d7365727665723a312e302f0000000000
16:34:55.303 [bitcoinj user thread] INFO org.bitcoinj.core.PeerGroup - Attempting connection to [127.0.0.1]:18333     (1 connected, 29 pending, 28 max)
Hostname of peer is 128.199.150.233
16:34:55.304 [bitcoinj user thread] INFO org.bitcoinj.core.Peer - Request to fetch block 5df3592f352825b51cf3891e54e739bc6ce2f335570cf285b9fde594506d9ecf
16:34:55.305 [bitcoinj user thread] DEBUG org.bitcoinj.core.BitcoinSerializer - Sending getdata message: 0b11090767657464617461000000000025000000d92f1b100102000040cf9e6d5094e5fdb985f20c5735f3e26cbc39e7541e89f31cb52528352f59f35d
Waiting for node to send us the requested block: 5df3592f352825b51cf3891e54e739bc6ce2f335570cf285b9fde594506d9ecf
16:34:55.306 [BlockingClient network thread for localhost/127.0.0.1:18333] ERROR org.bitcoinj.net.BlockingClient - Error trying to open/read from connection: localhost/127.0.0.1:18333: Connection refused (Connection refused)
16:34:55.306 [BlockingClient network thread for localhost/127.0.0.1:18333] INFO org.bitcoinj.core.PeerGroup - [127.0.0.1]:18333: Peer died      (1 connected, 28 pending, 29 max)
16:34:55.333 [PeerGroup Thread] INFO org.bitcoinj.core.PeerGroup - Waiting 973 ms before next connect attempt to [2620:6e:a000:1:43:43:43:43]:18333
16:34:55.339 [BlockingClient network thread for testnet-seed.bitcoin.jonasschnelli.ch/18.194.127.176:18333] DEBUG org.bitcoinj.core.BitcoinSerializer - Received 102 byte 'version' message: 7f1101000c04000000000000d77c0c5e00000000000000000000000000000000000000000000ffff9d22b767c4bc0c0400000000000000000000000000000000000000000000000081254911a30bb465102f5361746f7368693a302e31372e312f8ffc180001
16:34:55.340 [BlockingClient network thread for testnet-seed.bitcoin.jonasschnelli.ch/18.194.127.176:18333] INFO org.bitcoinj.core.Peer - Peer{[18.194.127.176]:18333, version=70015, subVer=/Satoshi:0.17.1/, services=1036 (BLOOM, WITNESS, NETWORK_LIMITED), time=2020-01-01 16:34:55, height=1637519}

Here is my code of main class file:

BriefLogFormatter.init();
        NetworkParameters params = TestNet3Params.get();
        try {
            String walletFileName = "wallet/forwarding-service-testnet.wallet";
            final File walletFile = new File(walletFileName);
            Wallet wallet = Wallet.loadFromFile(walletFile, null);

            WalletAppKit kit = new WalletAppKit(params, new File("./wallet"), "filePrefix");
        kit.startAsync();
        kit.awaitRunning();
        LegacyAddress to = LegacyAddress.fromBase58(params, "n2sPiCfFwjDmakuUDEPiTR9WKQkdkFAcaF");
        SendRequest req = SendRequest.to(to, Coin.parseCoin("0.001"));
        req.feePerKb = Coin.valueOf(0);
        req.ensureMinRequiredFee = false;
        try {

            Wallet.SendResult result = kit.wallet().sendCoins(kit.peerGroup(), req);
            System.out.println("Coins sent >> Transaction fee: " + result.tx.getFee());
        } catch (InsufficientMoneyException e) {
            System.out.println("Not enough coins in your wallet. Missing " + e.missing.getValue()
                    + " satoshis are missing (including fees)");
            System.out.println("Send money to: " + kit.wallet().currentReceiveAddress().toString());
        }
            peerGroup.stopAsync();

        } catch (Exception e) {
            e.printStackTrace();
        }

What I can do transfer bitcoin on my localhost peergroup among 2 or more wallets held with me?