I needed a hotend that supported the following: Phaetus Rapido UHF, Orbiter 2.0, Voron Tap, CPAP cooling, sensorless homing and filament cutting on my Voron Trident. The closest I found was the crown cooler github but this did not support cutting and the cpap cooling was restricted so I started my own design. 
This is version 4 and it is now in a state that I am happy with its performance, although I will update it in the future if issues are found.

It is assembled using m3 bolts and heat set inserts, with a m2 bolt to hold the blade mount to the cutter and a small m2 screw to hold the blade to the blade holder. The spring used in the cutter was a stock spring from my old ender 3 v2, any similar sized spring should work.

9 heat set inserts are required:

5 on the hotend mount for the orbiter, top duct/fan bolts, and cutting arm hinge.

4 on the duct for the bottom fan bolts and the two bolts that feed from the bottom back of the voron tap into the duct.

The blade used is a No.16 Xacto Blade, they are quite cheap from many sources. https://www.aliexpress.com/item/1005004971656248.html

There are two small pieces of PTFE tube inside the hotend mount to help guide the filament from the orbiter to the cutter, and from the cutter into the rapido.

On my 350 Trident, I cut with the following command, this will have to be adjusted for your machine.
[gcode_macro Cut_Filament]
gcode:
 M117 CUTTING
 G92 E0
 G1 X60 Y355 F8000
 G1 X0.2 Y355 F1000
 G1 X60 Y355 F8000
 PARK_NOZZLE

Revisions:
3/03/25: Added Hotend_mount_V5.1. Hotend has been reqorked to significantly improve airflow, directs air onto model in a similar manner to the Prusa Mk4.

I have yet to find any issues with the filament cutting. I am waiting for the Bigtreetech VVD multimaterial unit to be released, and once it is I will be sure to put it through the works.

2/03/24: Added Hotend_mount_V4.1 to solve filament getting caught on chamfer during loading.

27/04/24: Updated CPAP_Duct to improve flow, increase clearance, and reduce weight.