@Muay Thai I seem to never receive notifications when mentioned, so just seeing this now. I receive questions of this nature so often it's actually alarming. OP's question insofar as it relates to musculoskeletal soft tissue healing, BPC157 seems to have some efficacy. The rest, not so much.
I just want to make clear that the body's healing processes are shaped by eons of evolutions and won't be improved substantially by some Chinese peptides or outsmarted by those on internet bodybuilding forums. The body is already excellent at healing from (particularly acute) injuries.
GH is procollagenous (largely in the extracellular matrix) - this isn't something to expect to affect aches or pains (and certainly not to be useful for injury rehabilitation nor prevention) - but rather, this increases the strength of the bone-tendon attachment, with some increased mechanical advantage... i.e., this would translate in increased muscular strength as %1RM in a dynamic exercise. That's about all there is to that. (By the way, rhGH applied directly to the tendon definitely promotes tendon regeneration and growth; but this is probably not what OP wants - he's not going to do this sort of risky injection himself and we have no indication of tendon pathology nor any indication he's done even physical therapy of any sort, i.e., it doesn't even sound very serious).
Oxandrolone decreases wound healing time for skin grafts in burn patients (but with larger effects on weight regain, BMD, LBM). OP is not asking about wound healing; oxandrolone and AAS (yes, including T & Deca) increase markers of collagen metabolism, generally reflecting net collagen deposition. This is likely in the extracellular matrix. Of course, androgens also have unclear (some good some bad) effects on tendon. Let's not get to deeply down that rabbithole as it will just confuse people.
Deca benefits joint pain (partly by its particular procollagenous activity that is actually deposited into [at least rat] tendon) by its effects on the renin-angiontension-aldosterone system (I wrote about this here:
[link]). Unfortunately, this is a double-edged sword of sorts, as it also promotes cardiac tissue remodeling and pathological action by this same mechanism. I would not rely on procollagenous activity in the tendon to meaningfully reduce aches or nagging pain caused by, more likely, improper loading (e.g., exercise selection) and recovery.
Aside from proper planning and implementation of training (i.e., programming, exercise selection, changes to training variables), emphasizing rest/recovery (these would be my foremost considerations here personally)... you could try some BPC157 to promote musculoskeletal soft tissue healing (a "band-aid" of sorts). Works for some, not for others.