How big are the pots on the balcony?

In pots you could try
Scabious
Hosta's
Thalictrum Aquilegiifolium
Thrift
Papaver Poppies
Rosmary
Sempervivums

So long as you like daisy like flowers, and the balcony is in full sun, Arctotis, Dimorphotheca (Cape Daisy) and Dorotheanthus (previously Mesembryanthemum or Livingstone Daisies) should do well. Otherwise, Gypsophila, Iberis, Linaria, Matthiola, Penstemon, Phacelia in the annuals and biennials group.
Perennials such as Armeria, Pseudarmeria, Aubretia, Cordyline, Eryngium, Veronica, Papaver, Linum, Linaria, Stachys, Yucca.

If the balcony has railings could you not put some sort of wind shield up maybe out of greenhouse polycarbonate?

A thin hedge of Sea Buckthorn (yellow berries), Tamarisk (Pink flowers), Cotoneaster (white flowers - depends on variety) would give some wind cover for other plants that will flower. Variegated Privet also seems to do well at the shore and looks good all year round. All of those plants cna be kept in large pots at the back. Box can do well at the seaside but not direct gales/direct sea spray. Mediterranean Geraniums seem to do well all year round (expect in really cold winters), Crocosmia seem to love the seaside, but a balcony may be too dry - depends on where you live. I live about 1 mile from the sea and get the salty winds and some mild temperature compared to more inland. Properties in your neighbourhood can give you ideas on what does well.