The absolute accuracy in pressure sensors is important, the result is compared against the external reference device to get a deviation.
The relative accuracy in pressure sensors is also important, after the results under the different pressuresubstract the values of the external reference measurement seperately, the results are compared to observe their deviation.
Regarding choosing a pressure sensor, you have to know TCO as well.
TCO is the change in the pressure signal introduced by a change of the temperature.
Recommend you to choose BMP390 or BMP390L, which are the highest performance pressure sensors currently.