I am working in Macau and, in Macau, the only embassy is that of Portugal. I want to visit Paris, Amsterdam, and Switzerland. If I get a visa through the Embassy of Portugal, may I use it to enter these other countries (France, The Netherlands, Switzerland)? What if I get a Portuguese visa and I don’t visit Portugal?
Normally you need to apply to the embassy of the country that is your MAIN destination. So applying to the Portuguese embassy may get you rejected. However, if there is only one European embassy in the country, there may be special provisions for that and this embassy may be handling applications to other countries. I’m not sure how this would work for Macau as it’s kind of a special region in China. I imagine you would just have to apply to embassies in a different city though.
https://www.schengenvisainfo.com/where-to-submit-the-visa-application/ looks like it has some solid info.
From the General Consulate of Portugal in Macau:
Aplicando as regras em vigor, o Consulado-Geral de Portugal em Macau e Hong Kong processa os pedidos de vistos para pessoas que residam em Macau ou Hong Kong e que pretendam fazer uma viagem cujo destino principal ou cujo ponto de entrada seja em Portugal.
O Consulado Geral de Portugal representa a Alemanha, Áustria, Grécia, Eslovénia e Hungria para efeito de vistos Schengen em Macau.
Outras situações são apreciadas caso a caso.
In accordance with the rules in force, the Consulate General of Portugal in Macao and Hong Kong processes visa applications for persons residing in Macao or Hong Kong and intending to make a trip whose main destination or entry point is in Portugal.
The Consulate General of Portugal represents Germany, Austria, Greece, Slovenia and Hungary for Schengen visas in Macao.
Other situations are appreciated on a case-by-case basis.
They don't say they represent France (your entry point) or the other countries (possible main destinations) you plan to visit for Schengen visas.
If I were you, I would e-mail them to ask what are your options.