What should I do if I never hear back from professors for LORs?

I'm looking for postgrad admissions for next Fall and almost all the universities in US need atleast 3 LORs. I graduated back in 2021 from a university in different country and I have been working in the industry since then. In hope of getting a couple of academic LORs, i've reached out to a bunch of professors. I've heard from only once under whose supervision I did some research (from a different university), given i worked on the research remotely, he suggested that he won't be able to write a strong LOR.

I can still get a couple from my managers in the industry but I need a couple of strong academic LORs. I've also reached out to someone under whose supervision I'm working currently and they said they would be happy to write one after a publication but it's very unlikely that i'll be able to publish my current research before deadlines.

I will also be applying to Europe and hopefully not all of the universities/programs need LORs there but how should I move forward for the states?

Any advice would be highly appreciated. Thank you !