Is a backend API using node, mongo to slow for front end client to get results for live suggestions?

I want to write a series of small apps for myself as micro services. This is for practicality and self learning. I want these apps to be able to work independently, but build a separate frontend client that has a search bar that can find data across all of the services. I wanted to implement a live autocomplete with search results as the user is typing that will search across multiple databases.

My current approach was to split each app into two apps, backend API, and a frontend client. Have a common auth service that all of the apps utilize for authorization.

I think this approach would work fine except for speed and performance, which I am not sure about. It is a personal requirement of mine to be able to implement this search bar with autocomplete search results. This means it will have to make API requests to each service to get those results, it just feels like it might be too slow.

Also, in case anyone is wondering, I was planning on using node, express, and mongodb for backend. Probably go with node, express, vue or something for the front end.

Q. Does anyone have personal experience with the performance aspect of working with multiple APIs?

Q. If this approach is too slow, is there a better approach that still allows for a separation of the applications?