Well I don't think some people are familiar with these kind of stuff, so kindly asking the original mod author about publishing an already-converted SE version would be much more helpful for everyone imo.
Those who freely share mods shouldn't be expected to dote on requests from users for the rest of their lives, or even at all tbh. If they choose to do so, then they are very nice, and you're very lucky! The essential spirit of modding is taking the game into your own hands. Conversion takes about 5 minutes to learn and 5 more to perform; and that is not an overstatement of the general populace's capabilities, I assure you. All you need is YouTube or a friendly explanation. The tools are available in front of you. Leather Mashup Collection SE
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Extract BSA, use cathedral assets then CK.
Done it and work well.