Can these apply for naturalisation now?
Yes. Your wife applies for naturalisation using form AN. Your children must be registered using form MN1
If so how they can apply, online or paper application? Is paper application is still acceptable?
Online.
AN:
https://visas-immigration.service.gov.u ... onality-an
MN1:
https://visas-immigration.service.gov.uk/product/mn1
Is that the same online process as we did in ILR?
Similar
For a child can a solicitor or accountant act as referee ?
The application must be supported by two referees. One referee should be a professional who has engaged with the child in a professional capacity, such as a teacher, health visitor, social worker or minister of religion. The other referee must normally be the holder of a British citizen passport and either a professional person or over the age of 25. Each referee should know the child personally and should be:
• not related to the child
• not related to the other referee
• not acting as a solicitor or agent in connection with this application
• not employed by the Home Office
Advice is given based on my personal research and experience only. Do NOT contact me via private message for immigration advice