Have you tried mlb.com (online)? You might be able to see blacked out games via a VPN (virtual private network) by selecting out of market. Just select a route via an out of market location. It is a better and safer way, for example, if you are going to connect to a "public wifi" such as you find in hotels.
Mullvad gives access using up to 5 devices for about $5/month.
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