Not sure about zero-hour or short contracts in EU, but
> hire the artist as a freelancer.
this probably could be an issue due to investor's funding conditions (I've obly heard things like this, not experienced myself, so not sure).
> Alternatively, hire them through an employment agency.
This is super expensive, especially for the short contract like 3-6 months, easily could be around x2.5 comparing to hiring fulltime. So for a startup this is usually not an option, just because of the price.
> especially for the short contract like 3-6 months, easily could be around x2.5 comparing to hiring fulltime
Yes, when you hire people on short time contracts they quite naturally try to get paid enough to survive the gap until next contract, which makes the hour costs higher.
> hire the artist as a freelancer.
this probably could be an issue due to investor's funding conditions (I've obly heard things like this, not experienced myself, so not sure).
> Alternatively, hire them through an employment agency.
This is super expensive, especially for the short contract like 3-6 months, easily could be around x2.5 comparing to hiring fulltime. So for a startup this is usually not an option, just because of the price.