On average the Steller's sea eagle is the heaviest eagle in the world 15-20 lb average and large females can reached 26-28 lb Does it mean it's the world's Largest Eagle?

If this figure is correct, It's heavier than the Harpy eagle, average weight 8-18 lb. Steller's sea eagle is indeed the largest living eagle in the world; In zoology the heaviest is the largest, however the Philippine eagle is the world's largest living eagle species in terms of size or external measurements. The extinct Haast's eagle is the world's largest eagle that had ever lived, It's almost 50% larger than the largest eagle living today.