I have simmilar behaviour, usually several minutes delay. Seems to be delivered in batches, all at the same time.
Tested on Android 10 & Windows 10 Brave 1.16.76 & Android 10 Brave - Beta 1.18.51
Meanwhile Chrome works instantaneously
Also, sending from my phone to my desktop doesn’t seem to work at all. A couple days ago I sent 2 tabs from my phone and I’ve never seen them show up on my desktop.