I think the vast majority, if not all, splits sold in Europe are reversible. Currently, the majority are air source heat pumps, even if buyers, and often sellers, are unaware. That means that they pump 3-5 units of heat or cold for every unit of energy, making them, by far, the most economical heating and cooling available. They are cheap, too, like under 300€ in Spain, 400-500 for a top of the line Mitsubishi, or Daikin. Burning gas in the winter to heat a home is dumb.