New config.yml option: afk-timeout-command:

Essentials/src/main/java/com/earth2me/essentials/ISettings.java

@@ -210,6 +210,8 @@ public interface ISettings extends IConf {
 
     long getAutoAfkKick();
 
+    List<String> getAfkTimeoutCommands();
+
     boolean getFreezeAfkPlayers();
 
     boolean cancelAfkOnMove();

Essentials/src/main/java/com/earth2me/essentials/Settings.java

@@ -153,6 +153,7 @@ public class Settings implements net.ess3.api.ISettings {
     private Tag secondaryColor = DEFAULT_SECONDARY_COLOR;
     private Set<String> multiplierPerms;
     private BigDecimal defaultMultiplier;
+    private List<String> afkTimeoutCommands = Collections.emptyList();
 
     public Settings(final IEssentials ess) {
         this.ess = ess;
@@ -938,6 +939,7 @@ public void reloadConfig() {
         secondaryColor = _getSecondaryColor();
         multiplierPerms = _getMultiplierPerms();
         defaultMultiplier = _getDefaultMultiplier();
+        afkTimeoutCommands = _getAfkTimeoutCommands();
 
         reloadCount.incrementAndGet();
     }
@@ -1266,6 +1268,17 @@ public long getAutoAfkKick() {
         return config.getLong("auto-afk-kick", -1);
     }
 
+    private List<String> _getAfkTimeoutCommands() {
+        final List<String> commands = config.getList("afk-timeout-commands", String.class);
+        // commands.replaceAll(String::toLowerCase);
+        return commands;
+    }
+
+    @Override
+    public List<String> getAfkTimeoutCommands() {
+        return afkTimeoutCommands;
+    }
+
     @Override
     public boolean getFreezeAfkPlayers() {
         return getFreezeAfkPlayers;

Essentials/src/main/java/com/earth2me/essentials/User.java

@@ -825,18 +825,33 @@ public void checkActivity() {
         }
 
         final long autoafkkick = ess.getSettings().getAutoAfkKick();
+
+        // Checks if the player has been inactive for longer than the configured auto-afk-kick time.
         if (autoafkkick > 0
                 && lastActivity > 0 && (lastActivity + (autoafkkick * 1000)) < System.currentTimeMillis()
                 && !isAuthorized("essentials.kick.exempt")
                 && !isAuthorized("essentials.afk.kickexempt")) {
             lastActivity = 0;
             final double kickTime = autoafkkick / 60.0;
-
-            this.getBase().kickPlayer(AdventureUtil.miniToLegacy(playerTl("autoAfkKickReason", kickTime)));
-
-            for (final User user : ess.getOnlineUsers()) {
-                if (user.isAuthorized("essentials.kick.notify")) {
-                    user.sendTl("playerKicked", Console.DISPLAY_NAME, getName(), user.playerTl("autoAfkKickReason", kickTime));
+
+            // If `afk-timeout-command` in config.yml is empty, use default Essentials kicking behaviour instead of executing a command.
+            if (ess.getSettings().getAfkTimeoutCommands().isEmpty()) {
+                this.getBase().kickPlayer(AdventureUtil.miniToLegacy(playerTl("autoAfkKickReason", kickTime)));
+
+                for (final User user : ess.getOnlineUsers()) {
+                    if (user.isAuthorized("essentials.kick.notify")) {
+                        user.sendTl("playerKicked", Console.DISPLAY_NAME, getName(), user.playerTl("autoAfkKickReason", kickTime));
+                    }
+                }
+            } else {
+                // If `afk-timeout-command` in config.yml is populated, execute the command(s) instead of kicking the player.
+                for (final String command : ess.getSettings().getAfkTimeoutCommands()) {
+                    if (command == null || command.isEmpty()){
+                        continue;
+                    }
+                    // Replace placeholders in the command with actual values.
+                    final String cmd = command.replace("{USERNAME}", getName()).replace("{KICKTIME}", String.valueOf(kickTime));
+                    ess.getServer().dispatchCommand(ess.getServer().getConsoleSender(), cmd);
                 }
             }
         }

Essentials/src/main/resources/config.yml

@@ -484,6 +484,14 @@ auto-afk: 300
 # Set to -1 for no timeout.
 auto-afk-kick: -1
 
+# Define a set of commands the server runs when a player's AFK time elapses.
+# Set to [] to use Essentials' default AFK timeout kick behavior.
+#
+# Available placeholders:
+# {USERNAME} - The player's username.
+# {KICKTIME} - The time, in minutes, the player has been AFK for.
+afk-timeout-commands: []
+
 # Set this to true if you want to freeze players when they are AFK.
 # Other players or monsters won't be able to push them out of AFK mode.
 # This will also enable temporary god mode for the AFK player.