Stall is viable, even with gothitelle in the tier if you really press yourself, but this particular team doesn't make much sense. I would run recycle muk > tyranitar because even though it has less bulk it has more useful support moves like knock off and having to heal bell a rest user is bad for teams. Even if you ran assault vest muk, wish support is slightly better than supporting a rest user. Also chople berry is hugely unreliable.Pending
whether a stall team should be featured or not in the current state of the metagame, due to the viability of the playstyle and finding a solid stall team can prove very challenging and would need to be explored more to make a final decision on this team.
It also doesn't beat every hazard setter, as diancie will have a relatively easy time walling skarmory and killing giratina. This could be remedied by giving arceus defog but then gothitelle + diancie cores win.
smol edit: the ferrothorn set is good, and that mon in particular is also a really good place to start for stall due to its ability to beat most calm mind arceus forms, cm kyogre, and z-geomancy xerneas.
All in all a stall team would be appreciated but this aint it chief. At the moment I'm a fan of ditto stall and/or physically defensive sableye stall so both of those are good starting points for submitters.