There's tons of software edge blending tools...but they're way more expensive than resolume
Realistically if you plan enough you can edge blend your media in advance for your projectors, but that requires a lot of work
And yeah, the clients with the big $$ expect things their way, but realistically I find the clients without a lot of money to be the bigger pains in the ass, because they still want things their way buy don't have the money to pay for it! They want a huge show for tiny money, and they don't get that fully custom content (shot or motion graphics) will not cost $50.