After initial validation, target customers need the app to integrate with their ERP.. any suggestions?

I built my MVP (task management for distribution business) and started doing some initial validation with potential customers. All of these customers already had an ERP system in place.

The common denominator was:
"This could be useful for us, and we could give it a try.. BUT it needs to integrate with my ERP, I will not have my team spend time on duplicating data entry"

I started researching and there are some ERP's that have API funciontality out of the box, but a lot of +10 old ERP's don't have this available and customer would need to purchase a custom development for this.

Has anyone been in this situation before? How did you proceed? Did you went and create integrations with any ERP system a potential customer had?

Thanks!