There is first person which gives a full screen view and there is first person which puts the weapon, shield, etc onto the screen and moving the aiming reticule off center.
The result is 25-50% of the screen is covered by the shield/weapon and you have to learn to adjust your aim, it also seems to affect distance drop of arrows where out of weapon first person view I can 90% of shots calculate the drop so even if I miss to the side, the arrow is the right height but when weapons are shown the arrows seems to drop hugely faster so that long distance shots become almost impossible.
For now I've switched to 3rd person because I simply can't play in 1st person with the bow that useless and fighting vs cavalry with a shield that blocks 50% of the screen is super annoying when cavalry constantly weave to the left into the area the shield blocks from view. .