I doubt the EU will issue a blanket ban on Huawei. For one in a lot of countries the 5G rollout is already in an advanced status and Europe prides itself on being on the leading edge of wireless telecoms rollouts. For another the UK, which is the only Five Eyes nation in the EU, is bound to leave the block soon.
There is a possibility that some EU companies might push the EU towards adopting some kind of measures against Huawei though, because the other major 5G telecoms equipment vendors are located in Europe. I could see the EU engaging in some sort of tit for tat regulations and operate more on the anti-competition argument, say with fines, than with an actual ban on Huawei due to security considerations.
Especially after the scandal where the German Chancellor was spied upon by US intelligence I don't think the US's "security" arguments will have enough substance that anyone with two brain cells will care. Also a lot of people ignore this but much of the 5G market will not be in Europe. Or the USA.
Africa and Southeast Asia will be hugely important markets. They do not have the same amount of connectivity that other countries do and they rely, way, way lot more on wireless to conduct activities. In there China can easily win.
That is enticing but self-destructive approach as you have said in the underlined texts that China will probably be the biggest 5G market. There is an understanding between China and EU that guarantees Ericsson and Nokia's access to Chinese telecom market (about 30%). These two would be the casualty if EU overtly (straight ban) or covertly (anti-competition) hinder Huawei's access to EU. Let's be frank, Ericsson and Nokia feel more scared than happy if EU acts against Huawei, they may stand loosing more than gaining from Huawei's setback in Europe.