I love to tinker with suspension so I did it myself. Obviously the KTM upper fork legs will not fit the Varg triple clamps dimensionally, but KYB uppers will work just fine with the AER fork and it is a straight forward, reasonably priced change. You could even use the uppers from the stock KYB fork, but I opted for some bling and got Kashima coated ones. You should be able to get a recent AER fork (the newer the better, I'd look for 2025/26 ones) that was taken off a bike in exchange for some Pro/A-Kit forks for little money. Just a word of caution, you want a stock WP AER fork and not an WP aftermarket XAct Pro one as those usually have different threads and will not work with the KYB upper fork legs.
In general the current WP AER is a great fit for the Varg. Not only have those forks come a long way and work pretty good even stock, but the extra weight of the Varg actually helps offsets the extra friction. Also the Varg is actually a little front heavy and removing those 3lbs is more than noticeable. Last but not least the easily adjustable air spring is a great tool to give your Varg the feel you are looking for.
Michael