It is a fact that the British poured into Portugal lots of small arms in the quoted period, with an emphasis to the Peninsular war first years, when the quanties of firearms and other military gear brought in reached astronomic numbers. We must remember that Portugal had been military castrated by the first French invasion and consequent demilitarization ordered by their ocupying General (Junot). Also not to forget that Britain was already an industrialized nation and, besides their facility and (let's say) convenience to produce massive quantities of equipment, needed at all costs to avoid Napoleon from totaly controlling all peripherical continental countries, which would result in Britain's confinement to their territory.
However Portugal had kept a certain activity in the area so, for the period, you had weapons originated from Britain, locally copied from British patterns and also a determined quantity of genuine Portuguese stuff. Connoisseurs may easily distinguish the three sorts.
I have done some reading and also scanned a coulple pages from "AS ARMAS E OS BARÕES", written by Eduardo Nobre.
Here can be seen pictures of Portuguese pattern 1806, both in basic and variation versions.
One of these variations is the so called "trigger saber", distributed to officers comissioned to Army head staff, as well as to Engineers and Scouts.
The other variant with the brass hilt, has the legend VIVA PORTUGAL and is signed by a Portuguese (unlisted) smith.
The two sheathed ones are the basic light cavalry sabres, as per the 1806 armament regulation, which denote the following Portuguese characteristics:
The iron knuckle guard departs from the same level as the curved helmet (pommel). The langets are the only decoration in these weapons of plain lines. However their orientalist profile confirms a moorish inspiration.
Another typology of Portuguese sabres is the tang, that screws to the helmet (pommel), instead of being peened, was it was current in other models.
It is said that Europeans adopted the concept of curved blades from Moor cimitars, which were adapted to rapid horse combat.
In Portugal this type of sabre has achieved peculiar characteristics and was extensively produced and used both in the Peninsular war and various Portuguese civil wars during the first half of the XIX century.
It is also said, which is not new to you, that the blade curvature was essencial in a horse combat, often dealt with the opponents side by side. E. Nobre reminds us that the curvature of certain sabres was so exagerated that, when the soldier raised his armed hand to the level of his left shoulder, the sabre point would touch his right shoulder.
I hope i made myself understood ... and with good manners