What would cause water retention in both legs? All blood work have been done its all good. Did a urinalisis good. Has high blood pr. & diabetes.

Weak heart. Congestive heart failure needs to be ruled out. Kidney failure is also possible with long standing diabetes. Blood clots in the legs, excessive salt intake, poor blood pressure control, low Albumin levels need to be considered.
Angioneurotic oedema. Water retention in toth legs if equal common angioneurotic oedema, which also related to drug side effects and vascular disease. You'll need some further examination in the department of neurology and vascular surgery.