Witch Hazel
Yellow
Acacia.
The Chinese most commonly use the bud of the flower in their medical practice, in other countries it is mostly the flowers and leaves that are used for their healing properties.
Barberry
Yes
Cytisus or broom.
Japonica
Jasmine
In sub-tropical areas, allamanda cathartica is a soft shrub with clusters of bright yellow flowers at the tips of twigs. Not strongly fragrant, at least not in my garden.
magnolia
Sounds like a Berberis.
a Jasmine is a climbing shrub with delicate and fragrant white or yellow flowers. fro9m Persia