So here is a support we built. Following a similar idea you can build your own, and hang your own fun stuff on it.
At 3 meters long, our swing support has holders for three individual swings, or one big swing (three-four places) or a hammock.
It consists of a metal pipe (2' diameter), a wall-support (you may need two depending on your balcony), and 6 holders made of pipe-holders and eye bolts.
It is very stable and silent, great!
Note: If your balcony is short, please consider the danger of kids falling out of it from the swing. Do this swing only if sizes safe.
Step 1: Materials
1 Metal pipe 2'' diameter (3 meters in my case)
1 Metal scrap (round works best)
1 Metal pipe 1.5'' diameter (can be 20 cm short)
(you may need two wall supports depending on the balcony)
6 round pipe hugs
6 matching eye bolts
By using carabiners, the whole thing becomes modular. You can exchange the place of swings, or remove them altogether when you need the space beneath them. You can have one day the large all-family swing, and the other 3 smaller swings. Or remove all and hang your punching ball. Use carabiners in yours too.