Usage of appostive phrase

I came across this sentence when reading a newspaper.

• An information systems specialist who set up his own mobile app development company, Edward established Web Organic in 2019 and tapped contacts in the industry for help.

In this sentence, "an information systems specialist who set up his own mobile app development company" is placed at the beginning (in front of the subject)

In what conditions can an appositive phrase be placed forward? For instance, are the sentences below grammatically correct? (They both sound weird to me but I couldn't figure out their difference with the aforementioned sentence)

• 1 The president of the United States, Trump waged a trade war against China.

• 2 A fan of Michael Jordan, Jack flew to the US to watch his match.

It's an appositive, and as such, can appear before or after the noun.

Purdue Writing Lab:

An appositive phrase usually follows the word it explains or identifies, but it may also precede it.