razer blade 16 and 18 charging

You can use usb c power adapter up to 100 watt for example like MacBook power adapter (usb C), but only for something light that doesn’t involve the nvidia gpu like gaming. You might see warning windows (maybe I don’t have the 2023 model) but as long as you don’t do intensive tasks like I mentioned above you can ignore it, I think it’s to warn users that gaming using lower ac adapter might harm the battery (for discharging it while using).

You can purchase a gan charger from SlimQ life. They have 330w model on Indeigogo

The Slimq 330w doesn’t work at full power - the laptop gives errors and the battery discharges during use. 
 

I also believe a third party charger voids the warranty (I assume usb c might be ok, but I don’t think anything other than an official charger in the full power port is ok)