Could be its a loser, its just maybe too simple.
Two ways it can lose - buy order triggers but price falls back through the candle’s range and breaches the low. This triggers the sell order, which locks the trade into making whatever profit the sell order makes by the next close lower than the short entry, minus the loss incurred by the long trade since it opened (it is closed when the short order is closed).
So a loss is incurred if the new candle forms an outside range candle.
But then you re-set another pair of orders and start again. So the strategy is more likely to make a loss if there are more outside bars. Intra-day this isn’t something I’m familiar with but outside bars are not common long-term.