Unfortunately 1Password doesn't work. Not because of extension compatibility but seemingly because 1Password has an internal whitelist of trusted browsers that Orion is not included in. It's really unfortunate as there's been a community forum post about it for months[1], but it's never been addressed.
Dark Reader has worked perfectly fine for me though.
At least with 1P8 (and I can only speak to the Linux version), they have an opt-in file located in /etc/1password/custom_allowed_browsers (https://1password.community/discussion/comment/641837/#Comme...) although one will want to exercise caution about the ownership of the actual binary, as one can see in that thread
I haven't needed to try that on macOS but it may be worth a shot, given the shared Electron codebase
Then be sure to check that 1Password_rCURRENT.log mentioned in the thread, as it may provide at least more debugging info about why they're angry; that's how I found out how to fix my Firefox install (albeit not on macOS)
Dark Reader has worked perfectly fine for me though.
[1] https://1password.community/discussion/124112/support-for-or...