I do not think that this will qualify for a compostela, if this is important to you.
To qualify for a compostela, my understanding is that you need to walk the whole of the last 100km on a recognised Camino. In other words, for the Camino Ingles, walk the last 100km of the Camino Ingles, which you will not do, because you do not walk from Pontedeume to Hospital de Bruma where the La Coruna route of the Ingles joins the Ferrol route.
What you will do is walk the 76km or so from La Coruna to Santiago, which does not qualify for a compostela, unless you live on the La Coruna route, or you have walked 25km in your own country.
If you want to enjoy La Coruna, why don't you simply stay a night or two there before you take the train from La Coruna to Ferrol? The train journey from La Coruna to Ferrol is lovely, with about 75% of the journey being on the coast. It also passes by most of the walk you make from La Coruna until the sea disappears on the inland part of the La Coruna Ingles section, and in my view, viewing the sea from the train is probably more picturesque than walking uphill through the, not so picturesque, suburbs of La Coruna.
Final point. Almost half of the stage between Pontedeume and Betanzos is also by the sea, a wonderful walk round the estuary. And less than half the walk from La Coruna to Hospital de Bruma is by the sea. So what you are doing is substituting one walk by the sea for another, for a reason, I cannot understand?
If you are desperate for the walk from La Coruna, when you reach Hospital de Bruma, why not catch a taxi back to La Coruna, and then walk from there to Hospital de Bruma? The overlap will only be on the last 5km or so before Hospital de Bruma.