Though it may be possible for the next generation, (George's wife), to continue a career in a private capacity, I don't believe it would be viable for Harry's spouse.
Let's say she worked for a British pharmaceutical company in some capacity. If that company gained any advantage in the marketplace the British press would say it was because of her. If she was promoted (due to her own diligence) it would be said that it was because of the HRH.
The security at such a firm would be a problem. Knowing a Royal was working there, some bomb threats could be made by disturbed people just to enjoy the headlines. Fellow workers could very well object to a couple of RPO's being stationed on the premises every day. Reporters could grill fellow workers about Harry's wife, even attempting working undercover as new staff to get a story. I just don't believe employment in the private sector would be viable at all
George’s wife will be a Queen. She is not comparable to Princess Harry. Charlotte’s husband is a good comparison. I would assume that he will work outside the royal family.
As for her getting work “advantages”, who cares? The tabloid press has whined about Peter’s firm getting the Queen's 90th birthday party, that hasn’t stopped him. The tabloid press has whined about Zara getting BBC Sport personality of the Year, and getting several endorsement deals despite being in a low-profile sport, and despite not being as talented as some of her teammates(Mary King, William Fox-Pitt), yet she continues on. The tabloid press has whined about Beatrice getting hard-fought financial jobs despite not having a degree in finance, yet she continues on. The tabloid press has snarked about Eugenie getting employed in NYC by one of her best friends, but that didn’t stop her. The press noted that Harry was given the opportunity to fly Apache helicopters even though he had low entry grades that would normally disqualify him, that didn’t stop him. William flies helicopters even though his eyesight would normally have disqualified him for the RAF, that didn’t stop him. Edward attended Cambridge even though his grades weren’t good enough to be accepted, Philip called the admittance a royal “miracle”, that didn’t stop him. Princess Harry will get some tabloid whining in the beginning , then the tabloids will move on. She shouldn’t be held to higher standard than born royals who embrace all the advantages thrown their way.
I don’t think security will be a big problem. It would cost security more to have her be a full-time royal, where they have to check out the crowds at all her engagements at random places. If security can clear George’s school (a future king!), they can clear the workplace of a woman married to a younger son of a King.
That’s if she wants to work. Harry is independently wealthy, and Charles/William will continue to fund Harry’s luxurious life. It’s not like she’ll need to worry about paying the rent. If her and Harry have children she might wish to stay home with them. Or she and Harry might fall in love because of their mutual passion for traveling. Then she and him can spend a good chunk of time exploring the world. Maybe, even take up a part-time home in Africa.
With the abundance of working royals, Harry and his wife have the chance to seize their non-royal passions and live life to the fullest. As long as the carry-out part-time duties, they’ll be doing their fair share.