Not completely (rather no) because apple dropped from support all the iPad without official iPencil support.
Even if your 2018 MBP is HEVC capable, your limitation is in the iPad mini 4 hardware (very similar to the iPad Air 2).
But you can have it working again because for chance, during the Catalina beta 2 (around June), I catched a glitch by apple, and so if you use my "SidecarCore beta 9 patched file", you'll have a working Sidecar on your setup, but you should first update Catalina to the latest beta 11 and iPadOS to 13.1.2 and apply these preliminary steps:
- Boot from Recovery with CMD+R , open a recovery Terminal and type exactly: csrutil disable ; reboot
Then follow these tips to replace the file: https://forums.macrumors.com/threads/side-car-has-anyone-got-it-working.2184104/post-27807001
Followed your steps and got it working on my MacBook 11,2 and iPad Pro 11"! I started out with a wire but it kept working after I unplugged it, so I guess it works over WiFi as well