correct way as you already know I gather is new oil pan
after that, options include
helicoil,
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!
fumotousa.com
But again the proper fix is a new oil pan!, sucks but being honest!
after that, options include
helicoil,
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!

EZ Oil Drain Valve- The Easiest Oil Change!
EZ Oil Drain Valve- The Easiest Oil Change!
ezoildrain.com
Buy Fumoto® Valve Online | Replace Oil Drain Plug
By simply replacing your stock oil drain plug, you can drain your engine oil without tools or mess. Trusted by over 10 million satisfied customers, the original Fumoto Engine Oil Drain Valve continues to offer individuals, truck owners, marine engine mechanics, and industrial engine maintenance...
But again the proper fix is a new oil pan!, sucks but being honest!