Viltrox is now selling a new square metal lens hood for the 23mm/33mm/56mm f/1.4 series lenses. The hood is available in silver and black (52mm filter size):
"Viltrox square hood is a bayonet-mounted lens hood that fits only Viltrox 23mm 33mm 56mm series lenses. The square lens hood is better protecting the sensor from unwanted sun flare. Compatible with Viltrox 23mm/33mm/56mm f/1.4 series lenses (XF/E/Z/M). Filter size: 52mm.