The combination to avoid is mixing horned and unhorned entire tups with no ewes at tupping time. The hormones are raging, and the horned tup will quite likely kill the unhorned one.
They don’t fight wethers with the same intent. And tup lambs of the same breed will soon be shown their placce.
If you run more than one tup with ewes, make sure it’s a big area and there are plenty of ewes - more than 50, I would say, so there won’t be any days when there’s only one ewe cycling and they both want her, and a big enough area that they’ve got space to each take their chosen lady or ladies well away from the other.
Personally I wouldn’t risk a horned and an unhorned tup together with ewes at tupping time at all, although I know some people do.
What ex-BH used to do was combine groups of ewes, with their attendant tups, after first cycle. Usually by opening the gate between two fields and letting them mingle at their own pace. Most of the ewes will be in lamb by then anyway, but if either tup was firing blanks the other will catch the ewes on second cycle. By the time the tups are to come off they are used to each other and can be put in a field together without issue. These were commercial Texel-type tups, mind, which frankly are useless fighters anyway.
On the moorland farm we had Swaledale (impressively horned), Blue-faced Leicester and Texel-type tups. Not only did we keep the horned and unhorned tups apart at tupping time, but we never had just a single drystone wall between them. (Except once, and we lost a Leicester, so we learned.)
After tupping we would pen the tups all together in a very close space for several hours, then gradually increase the space. We didn’t give them enough room for anyone to get a run at anyone else until we were sure they’d got used to each other.
I’d always introduce tups who don’t know each other to each other that way, I think, whether it’s tupping time or not. But wethers and tup lambs shouldn’t be an issue.
I’m not sure about bringing a horned tup lamb in with unhorned mature tups... Either introduce him when he’s still a lot smaller and weaker than the adults, or not until he will clearly easily be dominant, and then not at tupping time.