Filioque (first introduced in Rome in 1014, not fully implemented on the peninsula until 1137)
Azymes (First appeared at the abbey of Cluny in the 1040s, implemented in Rome during the papacy of Leo IX, introduced in parts of Southern France around the same time)
Ultramontanism (Dictatus Papae, 1075)
Beards (Clean shaven clerics first started making their appearance in the west in the ninth century but it was a rare practiced and considered odd at the time. Mandated for Roman clerics by Hildebrand of Sovana/Gregory VII, but all of the popes up until the late twelfth century had beards, not to mention the 180 year period from 1522 to 1700 when every pope had a beard)
Baptism (Baptism by immersion was still the norm until the 13th century as attested to by Thomas Aquinas. Around this time baptism by aspersion was being implemented)
Statuary (3D statues didn't start appearing until the Renaissance, any statuary up until that point was bas-relief mostly relegated to niches around doorways)
Sign of the cross (Until the papacy of Innocent III the sign of the cross was performed in the west with three figures from right to left. In the early twelfth century the RCC began persecuting people who didn't accept the innovative practice of crossing oneself from left to right)
Rood screens (Universally present in Western churches until the Council of Trent in the mid sixteenth century after which most of them were removed in the ensuing decades)