I have found that bosals seem more popular in the USA, Ive not come across many here in the UK however I feel they are still worth a mention.
The link above gives a good photo of a bosal nose. Most are a firm material, quite often rawhide around the front of the nose and the reins or ropes both attach to the part under the chin.
I did recreate this type by attaching both reins to the chin ring on a headcollar, Sally quite liked this arrangement too.
What we do see a lot of are the rope halters and these attach at the same point under the chin to both reins.
If used very lightly there wont be a lot of pressure, however it would mostly be around the nose and muzzle. I do think if used from the ground the horse would feel some poll pressure too. A link below to how a rope halter looks on the horse. It is said that the knots are positioned for particular points on the horses head, therefore I imagine some would be comfortable and some would not like this halter.
https://www.viovet.co.uk/Hy-Rope-Halter/c26685/?quick_find=178496&utm_source=sag&utm_medium=organic&utm_campaign=surfaces_UK&gclid=EAIaIQobChMItdqw6cbN7gIVTe3tCh0KvgPWEAQYAiABEgIVYPD_BwE