correct way as you already know I gather is new oil pan
after that, options include
drill and re tap to next size up
have welded and re drill/tap
or weld in a fast drain that has a throw lever so never have to come out again
like one of these, folks been using them on 4 stroke Yamaha and cat sleds for yrs problem (along with tons of other vehicles used OFF ROAD) free to make draining oil easier, but can be used to solve a stripped plug too I would imagine,
maybe some JB weld to make it STAY in and then just drain using its valve!
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But again the proper fix is a new oil pan!, sucks but being honest!