Hi - to trace Edith Blanche Watson forward (born 17 July 1900) you would need to post her married name, if she had one. One of the people living in the IOM might have known her, or of her. It is also possible that she might have a MI in a family plot - perhaps with those same Watsons whose burials I posted yesterday:
[WATSON, Selena Ann 56 Marown 25 Feb 1932
WATSON, William 76 Marown 27 Aug 1941
WATSON, Ethel Lottie 7 Marown 9 Feb 1906]

You could also look for her death record, under the parish where she was living, on:
www.ManxBMD.com
If found, you could order her death cert from the Registry.

Sue