Libra is a stable coin. XRP is not backed by anything.
Libra is centralized. XRP is centralized.
Libra TPS - probably unlimited (since it is not a blockchain technology), XRP - 1500 TPS.
Libra will be restricted in some countries. XRP is not.
Exactly. Those are one of the key differences between Libra and XRP. While Libra's focus is to be a stablecoin for the masses, it nearly serves the same purpose as XRP. This is largely because, both cryptocurrencies are centralized aiming to bring micropayments to the world via the use of Blockchain tech. XRP may not be backed by anything, but it has wide-spread support from major Banks worldwide. In terms of scalability, XRP can perform nearly the same TPS as Libra since they're both centralized. Some tweaks here and there should make XRP as scalable as Libra.
Still though, the launch of Libra by 2020 is highly uncertain as Facebook gave a notice within the SEC that it may not launch after all. This is probably, because regulations are too fierce for Facebook to comply with each and every one of them for Libra's legality within the mainstream world. If Libra never launches, then XRP will be in the lead of centralized payments for a very long time.
Nonetheless, in case Libra becomes a success, it may have a hard time trying to overcome XRP since it has first-mover advantage like Bitcoin and Ethereum. Despite this, Libra could serve well as a stablecoin for the masses that would enable mainstream payments while XRP will be the ideal system for Bank-to-Bank transfers worldwide at the lowest costs possible. Both Libra and XRP are against the very foundations Blockchain technology was created for. Which is why, no one knows what their outcome will be in the future as they could either fail or succeed by then. In the meantime, XRP is doing well despite being a centralized cryptocurrency. Being the world's third largest cryptocurrency by market cap, has a lot to say about it. Just my thoughts