Hi partner,
It is possible.
You could use JS code to do this. For example, I want to open a contact form in popup window when I change the name field in my test entity form, I used the following code.
function openFormPop(){
var entityFormOptions = {};
entityFormOptions["entityName"] = "contact";
entityFormOptions["entityId"] = "8DA6E5B9-88DF-E311-B8E5-6C3BE5A8B200";
entityFormOptions["openInNewWindow"] = true;
entityFormOptions["height"] = 100;
// Open the form.
Xrm.Navigation.openForm(entityFormOptions).then(
function (success) {
console.log(success);
},
function (error) {
console.log(error);
});
}

Since you are using PCF control, just add the JS method in onchange event and have a try.
And in additional, you could even pass values as parameter to the popup form to set the values to fields.
For more details, you could refer to this doc.

https://docs.microsoft.com/en-us/powerapps/developer/model-driven-apps/clientapi/reference/xrm-navigation/openform
Hope it helps.
Best Regards,
Leo