You can easily climb the Daubenhorn from the top go the Gemmi Pass via the normal route which is a T3 hike involving a small glacier crossing and a short scramble at the top.
However by far the most exciting and rewarding route is via the Via Ferrata or the Daubenhorn Klettersteig (in German). It is a very difficult Klettersteig and demands endurance as well as experience and of course proper Via Ferrata equipment.
You can reach the start from the top of the Gemmi by descending a bit or you can walk up from Leukerbad. It is well marked. Allow 8 hours for the whole route including the descent down the normal route of the Daubenhorn. Watch the weather carefully as well.
We had great weather and took the whole day over it with lots of photo stops and a picnic on the top. We took the Gemmi lift and walked down to the traverse out under the face. It was spectacular the whole way and in September not too busy. The first section leads up to the top of the Swiss flag which you can see from far below in Leukerbad. This is a good picnic and rest spot and from here the proper vertical via ferrata climbing starts. There is an opt out route here which leads back down to the valley as well but it is still very vertiginous and not recommended. Better to bite the bullet and continue up the hair raising route to the top. In 2018 there was a big rockfall and the route had to be changed for the better. It makes an exposed traverse and then climbs up a spur on good quality rock to rejoin the old route and the famous cave via a wire bridge or Tyrollien. In the cave there is another short route choice. The harder route is more strenuous but far more enjoyable as it avoids a greasy dark wet slab.It is very short. After the cave it goes straight up a gully and traverses right spectacularly and climbs up some more ladders. At the top of this section there is a good resting spot but it is still a long way to the summit. Here too there is a short variation which is the most exposed of all and very scary or "lufftig"!After this airy ladder there is a bit of a walk and scramble until the final strenuous and practically overhanging ladder puts you out on the summit ridge. In total there are some 200m of ladders on the wall. The whole route is perfectly equipped and very well thought out. Don't forget to make a donation at the top to help fund the upkeep of this awesome klettersteig or via feratta up to the Daubenhorn summit.