If the Duke of York is offered from the start as King Consort of Scotland
Would he be ?
In OTL, Henry VIII wanted Mary to marry Edward in order to have a personal union under the Tudor dynasty. This is the reason for the Rough Wooing and for the betrothal between Mary and François.
If Henry VIII had a second son, would he offer him instead of Edward?
Obviously, the Scottish would prefer the Duke of York to the Prince of Wales in order to avoid personal union but would Henry VIII be satisfied with that?
And she would likely be raised in England, thus she would be Protestant
For that, you need a successful Rough Wooing and Mary being betrothed to Edward. If she is betrothed to the Duke of York instead of the Prince of Wales, I guess HE would be raised in Scotland as a Catholic.
Also, would the Duke of York be preferred over a French match? Of course, if there is no risk of personal union with England, the Scottish would not opt for a personal union with France. But, if the English offer an English prince but not Prince of Wales, the French can also offer a French prince but not the Dauphin.