

That’s a good tip, it’s a good idea to subscribe to a Lemmy instance that participates in Fediseer (IMO). It helps to keep spammy instances off your own instance hence lower spam posts overall.
A lot of spammers tend to spin up their own Lemmy instances just to spam the rest of the Fediverse, or they’ll create a ton of new accounts on an instance with lax admin/moderation to use for spam later.
You don’t even need to browse the Fediseer website directly, pretty much all Lemmy instances participating in Fediseer will have the “Guarantor” and “Endorsements” links in the sidebar of their homepage.
Assuming you are then you should be looking for a USD ETF. The ETF itself doesn’t have to be investing in U.S. based companies (and in fact there are many, many USD ETFs focused outside the US).
Keep in mind those are indexes, not ETFs. You are going to want to look for an ETF that is following the particular index(s) you are looking at. So for example the second index you mentioned does list one ETF that is following that index, see the main page for that index and click “Index-Linked ETPs”
https://www.msci.com/indexes/index/728912
The only ETF listed there is a EUR ETF, there may be no USD ETFs following that index. Your next step is trying to find a brokerage in the U.S. that allows you to invest in that ETF… Thing is, those brokerages will sell you access to invest in USD ETFs, not EUR. A ETF for EUR markets is primarily going to be offered in countries that trade in EUR.
Main point: Tons of indexes exist for different purposes but that doesn’t mean that ETFs exist that follow those indexes, let alone USD ETFs. For your purposes sure you can look at any indexes you are interested in just remember you’d still need to find a corresponding USD ETF that is following the index.
You may already know this, just keep in mind these indexes that measure “SRI”, or climate change, or concepts like that will measure this stuff in different ways that people don’t always agree with. For example the MSCI World SRI Index you linked has TESLA as one of its top investments, many would argue that Tesla/Elon Musk are not compatible with the idea of SRI.