In the third option, everything is very simple regarding skirmishes. This can be justified:
1) By the fact that we have sworn allegiance to a particular country. Therefore, it is our duty as a vassal.
2) By the fact that we are not vassals, but allies of one of the parties in the conflict. Military assistance is part of the agreement.
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Participation in the voyage can be justified by an interest in exploring new lands. Well, in the case of the third option, again. Although I'm not sure if it's worth sending a leader there.
Added 2 minutes ago
The Most Honourable Order of the Bath, more commonly known as the Order of the Bath[1], is a British order of chivalry founded by George I on May 18, 1725.
Where do we end up when we save the world?