Unless they remove support for local vaults from their mobile apps, you can continue using the classic self-synced method. I sync my 1Password vault across Android and Windows using SyncThing, using 1Password 7 and the legacy browser extension in Firefox. I don't get the inline 1Password prompt in password inputs, but that's the only disadvantage (Ctrl+Alt+\ brings up the password selector anywhere in the OS, not just the browser).

In fact, if you're okay with only editing/creating password entries on your phone, you don't even need to pay for the desktop app, because you can use it in read-only mode. The Android app has no limitation to editing local vaults, and it's pretty rare for me to actually have to set up new accounts these days, so I'm fine doing it on my phone. I considered paying for 1Password X (their online offering), but it's simply not worth $45 per year for that minor convenience. I can't complain at all, because I use 1Password completely for free.