You can use dialer and SMS apps in your work profile. Your administrator might also allow you to search for work contacts from your personal contacts and dialer apps on your device with Android 7.0 Nougat or later.
The policy that governs this behavior is Device Management -> Android Settings -> Apps & Data Sharing -> Sharing to other profiles == Allow content sharing from Work Profile to personal space. (Work Profile only)
Make or receive a phone call
Your administrator can specify a dialer app for you to use in the work profile on your device with Android 7.0 or later. This work dialer app keeps a call log of work calls only and relies on work contacts. Otherwise, all calls on your device are made and received through the default dialer app in your personal space.
Work profile dialer app specified by administrator
Default dialer app
Send or receive a text message
All text messages are sent and received through the default SMS app in your personal space, such as Hangouts.
When you send a text message to a contact using the SMS app in your work profile, you’ll get an alert that says You’re using this app outside of your work profile. The text message is sent from the device’s default SMS app in your personal space. If your contact replies, the text message response appears as a reply in your personal space. Conversations with contacts in your work profile are stored in the history in your personal space alongside your personal chats. Only the sender’s number is shown and their details remain hidden.