some of the dwarf conifers might be ok, but as you have found out there is the danger of them drying out and dying as a consequence.

I had a Rowan in a pot for 10 yrs then planted it out, it did ok but so much better in the ground.

Sorry to be a wet blanket but Ginko prefer full sun.have a look at

https://www.ornamental-trees.co.uk/trees-to-grow-in-pots

There's always Ilex crenata fastigiata but its a column rather than a standard tree shape.

Or you could have a go at bonsai - several people on Goy have done it.

Thanks Steragram- good to know. Right plant for the right place!
Klahanie- I bought a magnolia Stella ya a few years back tho king it was a 'small' tree! Oh how mistaken I was! Could try a miniature variety I suppose.

Lol - Mag.Stellata is not very tall, but sister is it wide...

I grow a lovely pittosporum in semi-shade. It's easy to control and attractive all year round. I don't think they like deep shade though. Mine has grown into the traditional 'christmas tree' shape but my friend trimmed the lower branches off hers and it has formed an umbrella shape. Both are attractive.

Thanks Klahanie- I will certainly look into that. My previous expereince with camellia is that got caught out by frosts and the flowers turned brown. Once the large hedge has been taken down I will then ascertain how windy or sheltered it is and how much sun it gets , how long for and whattime of day.
Pennyfarthing - A shrub is also an option so will look into that as well. Thank you for your suggestion.

My two best small trees in pots, in partial shade, are Prunus kojo-nai-ma and a Copper Beech which is easily kept trimmed.

Thank you Sheilabub. Will look them up.