ABP can help you in that point by offering amicroservice-compatible, strict module architecture where your module is split into multiple layers/projects and developed in its own VS solution completely isolated and independent from other modules. Such a developed module is a natural microservice yet it can be easily plugged-in a monolithic application. See themodule development best practice guide that offers amicroservice-first module design. Allstandard ABP modules are developed based on this guide. So, you can use these modules by embedding into your monolithic solution or deploy them separately and use via remote APIs. They can share a single database or can have their own database based on your simple configuration.
Microservice Solution Template
ABP provides a pre-architected and production-ready microservice solution template that includes multiple services, API gateways and applications well integrated with each other. This template helps you quickly start building distributed systems with common microservice patterns.