Taiwan and Hong Kong both use Traditional Chinese, but they do not share every character or every word. Software that offers only one "Traditional" switch will be wrong for someone, somewhere.
Characters
Some everyday words have different preferred glyphs. A converter aimed at Taiwan may pick 裡 where a Hong Kong setting prefers 裏. These are not random typos. They are regional standards.
Vocabulary
Taiwan Mandarin writing and Hong Kong written Chinese also differ in words, especially for government, transport and daily life. OpenCC "with phrases" types try to swap some of those terms. They will not localize an entire article into Cantonese written style.
What to choose in this converter
- Taiwan audience: Simplified to Traditional (Taiwan) or Taiwan with phrases.
- Hong Kong audience: Simplified to Traditional (Hong Kong), or Hong Kong to Simplified in the other direction.
The full list is in OpenCC conversion types. You can compare outputs side by side in the text converter.