Yeah, looking at the source, it doesn't seem to be XenForo, most likely a custom software, however XenForo could probably do something similar as it's pretty extensive.
Updated step by step tutorial:
1. Apply for staff & get approved as a helper/trainee
2. Climb the ranks until you get console access
3. Download the plugins
4. Upload them here
5. Profit(?)
Name of the plugin you want:
SapphireHistory - Punishment History
MCM Link: https://www.mc-market.org/threads/377680/
Price: $5
How it would contribute towards the betterment of the community: A great history plugin that hooks into LiteBans, which is used by a ton of servers. (You could even...
Name of the plugin you want : OverCraft | Play with an array of heroes and battle for victory!
Spigot Link : https://www.spigotmc.org/resources/overcraft-play-with-an-array-of-heroes-and-battle-for-victory.27860/
Price : 14.99 EUR
How it would contribute towards the betterment of the community ...
Name of the plugin you want: Hardcore Factions - UPDATE 7.0 - All in one [ SALE -20% ]
Spigot Link: https://www.mc-market.org/resources/5641/
Price: $85
How it would contribute towards the betterment of the community: I'm not 100% sure if someone already has this, but it would be useful to...