Indonesian nationals meet the nationality requirement for the 240-hour visa-free transit policy, provided that:
the traveler's itinerary continues to a third country/region,
the traveler holds a confirmed onward ticket or relevant proof for departure from an eligible port of entry, and
the traveler's valid international travel document has at least 3 months of remaining validity.
Once approved, travelers may stay within the full administrative areas of Tianjin and Hebei. As some provinces currently do not permit full-area stay, we suggest checking the applicable ports and permitted activity areas on the official website of the National Immigration Administration. At present, 65 ports in 24 provinces can process entry/exit formalities and the 240-hour temporary entry permit.
If the two flights belong to different airlines, it will not affect your eligibility for the visa-free transit policy. With a British passport and following the itinerary: Busan-Beijing-Hong Kong, you are eligible for a 240-hour visa-free transit.
Under the 240-hour visa-free transit policy, the last country (or region) before entering the Chinese mainland and the first country (or region) after leaving the Chinese mainland must not be the same.
According to the itinerary you described — Geneva-Paris-Beijing-Paris, this route does not meet the requirements of the 240-hour visa-free transit policy.
However, if you travel directly from Geneva to Beijing without a stopover in Paris, and your itinerary is Geneva-Beijing-Paris, and you hold a British passport, then your trip meets the conditions for applying for 240-hour visa-free transit. Please note that the final decision is subject to on-site inspection and approval by the immigration authorities.