Maker of Elite Bionics Framework here.

If you use EBF together with EPOE-Forked, then FSF-ABE suddenly becomes incompatible. This is due to some RimWorld limitations.

The solution is unclear (at least to me), and will need to be talked through.

Both mods patch into vanilla bionics, and when multiple same things get added by patching, it confuses EBF and throw the error.

As for regularly having both EPOE and ABE together without conflict, would be the defNames duplicates and the stats of the advanced bionics as we have different approaches to balance.

There are various solutions, each with their pros and cons, but for flexibility purposes, there are other mod interactions that would need to be considered, alongside if both mods have patches inside another mod and cause double patching, etc.
This is kind of on my "to-do" list regarding enhanced compatibility for a long time, albeit on a lower priority right now.

Minor clarification: it does not confuse EBF, but it definitely confuses the game; the errors are thrown by the game itself before entering the main menu.

has this been fixed?

Try xeno biology Patcher, i don't use EBF, but i use an archotech mod from the same person, and while it does not exactly "fix the problem" it does allow you to avoid the issue that breaks ABE/EPOE and oddly for me ADS2 when they are all used together. It basically allows you to stick any prosthetic part on anything/anyone; which is a feature i didn't particularly want, but it was the only way i could find to fix the issue i had.

To clarify what the problem is, when some people added new prosthetics to the game; they unfortunately didn't actually always add new ones to the game, they edited the existing ones that were already in the game. (why they would do this i cant begin to fathom as it guarantees incompatibility with any other mod that does the same.) What this patcher does is what the original modders should of done in the first place and creates a unique body part label for each added item. This way each one has a different label and the game doesn't explode.

With the update of v4.4.6, added compatibility patch for [FSF] Advanced Bionics Expanded. Was done more as a curiosity project and a break from my own personal race mod.
We have spoken with the author of ABE, and exchanged ideas. The conclusion that the ratio of least effort to best consistency, was to alter mostly from EPOE-Forked's side, and ABE now adds UI icons to their surgery bills.
One principle that EPOE-Forked had when it came to Archotech tier bionics, is that we do not touch it is for sake of player's choice of Archotech bionic mods, which is why Advanced bionics are at 135%. Since ABE has Archotech included, it was no longer a concern to bump the rest of non-overlapping Advanced bionics to fit in with the combined mods.
All changes are only applied if ABE is active.

When that mod is active, the major effects listed below:
* EPOE-Forked's overlapping advanced bionics, surrogate and synthetic organs are removed. Existing ones in pawns' bodies during mod swaps will become debug versions to avoid pawn death.
* EPOE-Forked's advanced bionics research is removed and now uses ABE's version.
* EPOE-Forked workbench is forcefully disabled, and crafting method is forcefully set to "Direct Crafting Only".
* Research tab rearrangement. ABE's research are moved into EPOE-Forked's prosthetics tab.

If running both mods at the same time, the users will agree to the following:
* EPOE-Forked and ABE not liable to any errors generated with other mod interactions due to running both mods.
* EPOE-Forked and ABE not liable to texture inconsistencies due to running both mods.
* EPOE-Forked and ABE will not attempt re-balancing stats to each other when both mods are active. Requests for this situation will be ignored by both parties.
* EPOE-Forked and ABE will continue their respective independent development of their mods, and not liable to testing, checking or notifying each other if a new interaction conflict may appear.

If things break, there will not be any priorities in fixing it due to the already crazy idea of making two overlapping bionic mods work alongside each other.

I don't suppose it'd be possible to patch back in recipes to assemble advanced bionic parts from normal bionic parts back, would it?