What transportation does the Eurail Global Pass cover in Berner Oberland?

All depends on where you want to go. You get a 50% discount on the Schilthornbahn above Muerren, but only 25% on the train above Wengen. Discounts are the same as a Swiss Travel Pass. You don't say how long you will be in Switzerland total. The continuous pass is in 1 month or 2 month varieties, so which will you get?

We’ll be 17 days in Germany, 9 days in Switzerland, 7 days in Austria, then 4 days in Germany.

I was planning on the 2 month Eurail continuous pass since it’s not much more than the one month.

We want to go up to the Shilthorn and Jungfrau. Hiking from kleine Scheidegg and Murren.

The Jungfraujoch will cost you 171 CHF r/t per person from Wengen with the Eurail Pass

If you know your exact itinerary and plans then you can just go to the train websites and see how much all of your tickets would cost and then compare that to the cost of the Eurail Pass to see if you save any money - but I'm guessing it wont be cheaper.

As a general rule, with a stay of 3-6 weeks you rarely save money buying a Global continuous pass, even if you get the age discount for being under 28 or a senior. However it should be noted that you are picking the three best countries to use the pass in because they generally don't require pass holders to purchase an additional "seat reservation fee" and trains tend to be expensive along with most other things in those countries, so it might make sense to look at one of the Eurail Flex passes that allow you 10 days of travel in 2 months or 15 days in two months, etc. That way you aren't getting penalized on days when you don't get on a train, or you only ride a cheap regional train for 40 minutes. You can pick which days to use your pass allotment.

I'm pretty sure the Eurail Passes now cover the train rides from Interlaken up to Grindelwald and Lauterbrunnen but no further. Any other lifts, gondolas or trains up there would cost extra but you might get a discount. Also remember they are very expensive which is why people pull their hair out trying to figure out which Swiss pass to get.

Maybe get the 10 day Flex Eurail Pass to cover your relocation trains over the total five weeks and then add the 4 day Berner Oberland Pass to use when you are staying in that area.

Also note that if you did choose the flexi version of a Eurail Pass, you would not need to used a counted travel day to get a discount on the higher portions of the Jungfraujoch or Schilthorn transport (e.g. if the Muerren-Schilthorn roundtrip gondola is the main transport you use in one day) but then would not have any coverage of lower-level transport on that day.