Note that this is specific to European airports as listed in the question. It is not applicable worldwide as pointed out by @jpatokal.
Yes, according to this European directive:
4.1.3 Screening of liquids, aerosols and gels (LAGs)
4.1.3.1 LAGs carried by passengers may be exempted from screening with LEDS equipment upon entry to the SRA in the following cases:
(a)
if the LAG is in individual containers with a capacity not greater
than 100 millilitres or equivalent in one transparent resealable
plastic bag of a capacity not exceeding 1 litre, whereby the contents
of the plastic bag fit comfortably and the bag is completely closed;(b)
if the LAG is sealed in a dedicated STEB upon purchase locally at the
airport airside;(c)
if the LAG in a STEB originates from another EU airport or an aircraft
of an EU carrier and is resealed in a dedicated STEB before leaving
the security restricted area of the airport;(d)
if the LAG is screened locally with LEDS equipment airside and is then
sealed in a dedicated STEB.
LAG: Liquids Aerosols and Gels
STEB: Secure Tamper-Evident Bag
Ensure that the duty free item is sealed in a STEB at OPO with the receipt visible inside the bag.
Credit:stackoverflow.com‘