Errant is a reboot of a comic called Fan Dan Go, which you can still actually read on Drunk Duck.
People who have read Errant first and then read Fan Dan Go tend to say that it's like reading a weird off-brand bootleg of Errant, where there are most of the same characters, but everyone's just a bit "off". The art and storytelling are way worse for sure.
Examples of Fan Dan Go panels:
Examples of Errant panels:
The art difference is subtle, but the colours are a bit more cohesive and warmer, the proportions tend to be more pleasing with more sense of mass, and lines feel more deliberately placed.