What do you mean by "across wallets"
Are there any tools for privately tracking spending across wallets? https://bitcoinpolis.gitlab.io/posts/2022/04/29/private-finance-tracker.html
Discussion
I use many wallets (mostly Lightning), and ideally I could keep track of all of my spending, no matter which wallet I use. But I think even if it just works inside one wallet, that's a good start.