Update cross chain wallets docs with crossChainWallets config step (#970)

update cross chain wallets docs with crossChainWallets config step

Author: 0xmaayan

apps/nextra/pages/en/build/sdks/wallet-adapter/x-chain-accounts.mdx

@@ -86,7 +86,7 @@ import { setupAutomaticSolanaWalletDerivation } from "@aptos-labs/derived-wallet
 
 setupAutomaticSolanaWalletDerivation({ defaultNetwork: Network.TESTNET }); // this is the Aptos network your dapp is working with
 
-.....
+...
 
 <AptosWalletAdapterProvider
  dappConfig={{
@@ -96,6 +96,19 @@ setupAutomaticSolanaWalletDerivation({ defaultNetwork: Network.TESTNET }); // th
   {children}
 <AptosWalletAdapterProvider/>
 ```
+
+### Set `crossChainWallets` dapp config prop to `true` fot the `AptosWalletAdapterProvider`
+
+```tsx filename="WalletProvider.tsx"
+<AptosWalletAdapterProvider
+ dappConfig={{
+    network: Network.TESTNET,
+    crossChainWallets: true,
+  }}
+>
+  {children}
+<AptosWalletAdapterProvider/>
+```
 </Steps>
 
 </Tabs.Tab>
@@ -136,7 +149,7 @@ import { setupAutomaticEthereumWalletDerivation } from "@aptos-labs/derived-wall
 
 setupAutomaticEthereumWalletDerivation({ defaultNetwork: Network.TESTNET }); // this is the Aptos network your dapp is working with
 
-.....
+...
 
 <AptosWalletAdapterProvider
  dappConfig={{
@@ -146,6 +159,19 @@ setupAutomaticEthereumWalletDerivation({ defaultNetwork: Network.TESTNET }); //
   {children}
 <AptosWalletAdapterProvider/>
 ```
+
+### Set `crossChainWallets` dapp config prop to `true` fot the `AptosWalletAdapterProvider`
+
+```tsx filename="WalletProvider.tsx"
+<AptosWalletAdapterProvider
+ dappConfig={{
+    network: Network.TESTNET,
+    crossChainWallets: true,
+  }}
+>
+  {children}
+<AptosWalletAdapterProvider/>
+```
 </Steps>
 </Tabs.Tab>