public transport – How to get from Geneva airport to Metabief?

Google Maps finds no link between these points. suggests taking trains to Vallorbe, then a taxi from Vallorbe to Métabief.

(Actually, rome2rio suggests a taxi from the train station just before Vallorbe, but it will probably be easier to find a taxi in Vallorbe, which is a bigger station).

As noted in the comment thread under your previous question, this taxi ride is not long, but as it crosses a border, you have to agree on a price with the driver before you go up.

Otherwise, if you do not want to live a cross-border taxi adventure in French-speaking Switzerland, you can take a train to Frasne on the French side, then the Frasne bus to Metabief. (You have already found the times for this bus).

It will probably cost more because you will need the Lausanne-Frasne TGV rather than a local Swiss train and certainly slower. Note that the TGV requires a reservation, but on the other hand, you should not worry about flight delays because the first connection you can get leaves Geneva-Airport only anyway. Arriving at Frasne at 13:14, you have an hour and a half to kill before the bus to Jougne at 14:49.