I found a post about Brave last year, someone mentioned a solution, you can try it.
I started a new Brave wallet, cleared Brave’s cache and reset my MetaMask account. I then disabled crypto wallets in brave. The MetaMask extension in Brave is now working. I would start by downloading the legacy extension, and then disabling “load crypto wallets on startup” in Brave settings. If doesn’t work, you can then try clearing Brave’s/Chrome’s cache and resetting your MetaMask.
-----------by jiteshj
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