As of my last update in September 2021, the scenario you propose, where Meghan (the Duchess of Sussex) remarries Prince William and becomes queen in the same manner as Camilla (the Duchess of Cornwall) did, seems highly improbable and even impossible due to various legal, constitutional, and historical factors.
It's important to clarify the titles and positions of the individuals involved. Prince William is currently the Duke of Cambridge and second in line to the British throne, after his father, Prince Charles. Meghan Markle, on the other hand, ceased to be a senior working member of the British royal family after she and Prince Harry stepped back from their official duties in early 2020.
Meghan Markle is not a member of the British royal family in an official capacity anymore. She and Prince Harry relinquished their positions as senior working royals and are leading independent lives. While they remain members of the royal family, their decision to step back means they are no longer actively representing the Queen or carrying out official duties on her behalf.
Even if Meghan were to remarry Prince William, it would not automatically grant her the title of queen. In the United Kingdom, the spouse of a reigning monarch becomes a queen consort, not a queen regnant. A queen consort is the wife of a reigning king, but she does not hold the same powers and rights as a queen regnant, who is the ruling monarch in her own right.
The British line of succession is governed by laws, including the Act of Settlement 1701 and the Succession to the Crown Act 2013. As it stands, the line of succession is based on a mixture of common law, statute law, and constitutional convention. Prince William is second in line to the throne, and his position is unlikely to change unless there is a significant event, such as the abdication or passing of his father, Prince Charles.
The case of Camilla, the Duchess of Cornwall, is different from Meghan's hypothetical scenario. Camilla married Prince Charles, who is the heir apparent to the throne, after he divorced Princess Diana. Camilla's title is a sensitive matter due to the historical context of her relationship with Prince Charles, which led to public controversy and concern.
Any changes to the line of succession or the rules governing the monarchy would require significant legal and constitutional changes, which are difficult to achieve. It would involve altering centuries-old laws and traditions, which would likely require widespread support from the British public, the government, and the Commonwealth nations.
The scenario you propose, where Meghan remarries Prince William and becomes queen in the same way Camilla did, seems highly unlikely and implausible based on the current state of the British monarchy and the legal and constitutional considerations surrounding it. The British royal family's workings are deeply rooted in tradition and historical precedent, making such a change improbable in the foreseeable future.
