If it is not made public, it will have no effect.
Only if the earlier application is filed in China National Intellectual Property Administration, China, will it become a conflicting application of the latter application, which will affect the novelty of the latter application.
It doesn't matter if you apply abroad.
In the case that Taiwan Province Province and the mainland do not recognize each other's priority, you only need to apply in the mainland before the application of Taiwan Province Province is made public, and you can get the patent right.
Review guide page 155
2.2 the application of contradictions
According to the second paragraph of Article 22 of the Patent Law, when judging the novelty of an invention or utility model, the patent application documents or announced patent documents for the same invention or utility model submitted to the * * * Patent Office before the filing date and published by * * * after the filing date (including the filing date) damage the novelty of the patent application filed on the filing date. For the sake of simplicity, when judging novelty, such patent applications that damage novelty are called conflict applications.
It can be seen that the conflicting application must meet two conditions, 1, which is filed in the State Patent Office and published.